feat(chapter): preserve source-site order in chapter list (0.52.0)

The user-facing chapter list ordered by (number ASC, created_at ASC),
which broke the source site's order in two ways: non-numeric entries
("notice. : Officials") parsed to number=0 and clustered at the top,
even though the site placed them mid-list, and variants sharing a
number ("Ch.14 : PH" / "Ch.14 : Official") were torn apart by the
created_at tiebreak.

Capture each chapter's position in the source DOM as `source_index`
(0 = first = newest on this site) on every crawler sync, including the
UPDATE branch so a new chapter prepended on the source shifts every
existing row down by one on the next tick. The list query reverses
this with `ORDER BY source_index DESC NULLS LAST, number ASC,
created_at ASC` so the oldest chapter appears first, variants stay
adjacent in the order the site shows them, and non-numeric entries
land where the site placed them. User-uploaded chapters and pre-
migration rows keep their NULL source_index and fall through to the
prior number/created_at tiebreak via NULLS LAST.

The reader's client-side `[...chapters].sort((a,b) => a.number - b.number)`
is dropped; prev/next now walks the server-ordered array positionally
so it traverses variants and non-numeric entries in display order.

Existing data populates on the next cron tick or via admin force-resync.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.env.example

@@ -1,20 +1,30 @@
 # Copy to .env for `docker compose up --build`. Local-dev runs (cargo run
 # / npm run dev) read backend/.env if present, or pick up the variables
 # from your shell.
+#
+# Production note: COOKIE_SECURE=true (the default below) makes browsers
+# refuse to send the session cookie over plain HTTP. Run with a TLS-
+# terminating reverse proxy (Caddy, Traefik, nginx) in front — the
+# compose file here doesn't ship one. Local/dev runs without HTTPS
+# should set COOKIE_SECURE=false.
 
 # ----- Postgres -----
 # These are read by the Postgres container *and* by DATABASE_URL below;
 # changing them after the first boot won't migrate existing data, so set
 # them up front for any new deployment.
+#
+# POSTGRES_PASSWORD is REQUIRED — docker-compose.yml fails fast if it
+# isn't set in this file, to prevent a deploy without an .env booting
+# Postgres with a publicly-known credential.
 POSTGRES_USER=mangalord
-POSTGRES_PASSWORD=mangalord
+POSTGRES_PASSWORD=change-me-to-a-strong-random-string
 POSTGRES_DB=mangalord
 
 # ----- Backend -----
 DATABASE_URL=postgres://mangalord:mangalord@postgres:5432/mangalord
 BIND_ADDRESS=0.0.0.0:8080
 STORAGE_DIR=/var/lib/mangalord/storage
-RUST_LOG=info,mangalord=debug
+RUST_LOG=info,mangalord=debug,chromiumoxide::conn=off,chromiumoxide::handler=off
 
 # ----- Auth / cookies -----
 # COOKIE_SECURE controls whether the `Secure` flag is set on the session
@@ -29,6 +39,13 @@ COOKIE_DOMAIN=
 # get reaped lazily.
 SESSION_TTL_DAYS=30
 
+# ----- Auth brute-force rate limits -----
+# Token-bucket budget shared across /auth/login, /auth/register, and
+# /auth/me/password. Set per_sec=0 to disable (e.g. behind a
+# rate-limiting reverse proxy that already enforces a budget).
+AUTH_RATE_PER_SEC=5
+AUTH_RATE_BURST=10
+
 # ----- CORS -----
 # Comma-separated origins allowed to call the API with credentials.
 # Default is empty: same-origin only. Set when frontend and backend live
@@ -44,6 +61,69 @@ MAX_REQUEST_BYTES=209715200
 # Default 20 MiB.
 MAX_FILE_BYTES=20971520
 
+# ----- Crawler download safety -----
+# Hosts the crawler is allowed to fetch images/covers from, in addition
+# to CRAWLER_START_URL's host and CRAWLER_CDN_HOST. Comma-separated.
+# Defends against SSRF via scraped <img src="http://10.0.0.1/...">.
+CRAWLER_DOWNLOAD_ALLOWLIST=
+# Bypass the host allowlist entirely. Intended for sources that shard
+# images across numbered CDN subdomains (cdn1/cdn2/…) where enumerating
+# every host upfront is impractical. The private-IP / localhost / non-
+# http(s) scheme defenses STAY ON — a scraped <img src="http://10.0.0.1/">
+# is still refused with this flag set.
+CRAWLER_ALLOW_ANY_HOST=false
+# Hard cap on a single image body. Default 32 MiB.
+CRAWLER_MAX_IMAGE_BYTES=33554432
+# Max manga detail fetches per metadata pass (both the in-process daemon
+# and the `bin/crawler` CLI). 0 means no cap — let the source walker run
+# to completion. Useful for capped test runs against a new source.
+CRAWLER_LIMIT=0
+# Path to a system Chromium binary. When set, the crawler skips the
+# bundled-fetcher download. Required on platforms without a usable
+# upstream Chromium build (notably Linux_arm64 / Raspberry Pi). On
+# Debian: /usr/bin/chromium-headless-shell or /usr/bin/chromium. On
+# Ubuntu the package is chromium-browser (different path). Pair with
+# `docker compose build --build-arg INSTALL_CHROMIUM=true backend` so
+# the image actually contains the binary.
+CRAWLER_CHROMIUM_BINARY=
+
+# ----- Crawler TOR proxy + recircuit -----
+# The compose stack ships a `tor` service (dockurr/tor) and defaults
+# CRAWLER_PROXY to it, so by default all crawler traffic exits via the
+# TOR network. To opt out, set CRAWLER_PROXY= (empty) AND
+# CRAWLER_TOR_CONTROL_URL= (empty) below — the tor service can stay
+# running, it just won't be used.
+#
+# Going through TOR adds latency to every fetch; image downloads in
+# particular slow noticeably. The win is on sites that rate-limit or
+# fingerprint by exit IP — NEWNYM recirculation makes a fresh exit
+# cheap to reach for.
+#
+# CRAWLER_PROXY: SOCKS5(h) URL. Use `socks5h://` (not `socks5://`) so
+# DNS resolution also goes through TOR, avoiding leaks via the host's
+# resolver. Leave unset to talk to the upstream directly.
+CRAWLER_PROXY=socks5h://tor:9050
+# Control-port URL for SIGNAL NEWNYM ("get a fresh circuit"). Triggered
+# automatically on bad pages (broken-page body, missing #logo) and on
+# the Unauthenticated session probe outcome. Leave unset to disable
+# the recircuit feature (the SOCKS proxy still works).
+CRAWLER_TOR_CONTROL_URL=tcp://tor:9051
+# Max NEWNYM-and-retry cycles per recircuit-eligible failure. Default 3.
+CRAWLER_TOR_RECIRCUIT_MAX_ATTEMPTS=3
+
+# ----- TOR control-port password -----
+# Shared between the bundled dockurr/tor service (which hashes it into
+# its HashedControlPassword) and the backend's
+# CRAWLER_TOR_CONTROL_PASSWORD. REQUIRED — docker-compose.yml fails
+# fast if absent. Generate a strong random string; rotate by setting
+# a new value and restarting both `tor` and `backend`.
+#
+# Operators running their own non-dockurr tor daemon with cookie-file
+# auth can ignore this var and instead set
+# CRAWLER_TOR_CONTROL_COOKIE_PATH on the backend — the TorController
+# prefers cookie when both are present.
+TOR_CONTROL_PASSWORD=change-me-to-a-strong-random-string
+
 # ----- Frontend -----
 # The frontend container runs SvelteKit's Node adapter on :3000 and
 # proxies /api/* to BACKEND_URL via src/hooks.server.ts. In compose the
@@ -51,3 +131,8 @@ MAX_FILE_BYTES=20971520
 # internal docker network. Override only if you're running the
 # frontend container against a backend somewhere else.
 BACKEND_URL=http://backend:8080
+# Per-request wall-clock cap for the /api/* reverse proxy (milliseconds).
+# Default 300000 (5 min) covers a typical 200 MiB chapter upload over
+# 25 Mbps; raise for users on slower upstream links or lower if a
+# tighter front proxy already bounds the request lifetime.
+BACKEND_PROXY_TIMEOUT_MS=300000

.gitea/workflows/deploy.yml

@@ -3,13 +3,13 @@ name: deploy
 on:
   push:
     branches: [main]
+  pull_request:
+    branches: [main]
   workflow_dispatch:
 
 jobs:
   test-backend:
     runs-on: ubuntu-latest
-    container:
-      image: rust:1-slim
     services:
       postgres:
         image: postgres:16-alpine
@@ -26,10 +26,18 @@ jobs:
       DATABASE_URL: postgres://mangalord:mangalord@postgres:5432/mangalord
     steps:
       - uses: actions/checkout@v4
-      - name: Install build deps
+      # ubuntu-latest has node (so JS actions like checkout/cache run) but no
+      # Rust. We intentionally avoid `container: rust:1-slim` because act_runner
+      # runs JS actions with node *inside* the job container, and the slim Rust
+      # image ships no node (checkout would fail with exit 127).
+      - name: Install Rust + build deps
         run: |
-          apt-get update
-          apt-get install -y --no-install-recommends pkg-config libssl-dev ca-certificates
+          set -eu
+          SUDO=""; [ "$(id -u)" = "0" ] || SUDO="sudo"
+          $SUDO apt-get update
+          $SUDO apt-get install -y --no-install-recommends pkg-config libssl-dev ca-certificates curl
+          curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y --profile minimal --default-toolchain stable
+          echo "$HOME/.cargo/bin" >> "$GITHUB_PATH"
       - name: Cache cargo registry and target
         uses: actions/cache@v4
         with:
@@ -63,6 +71,18 @@ jobs:
   build-and-push:
     runs-on: ubuntu-latest
     needs: [test-backend, test-frontend]
+    # PRs only run the test jobs; build + deploy are reserved for
+    # post-merge pushes to main.
+    if: github.event_name != 'pull_request'
+    # Build on the host docker daemon directly (docker-outside-of-docker):
+    # the runner shares the deploy host's daemon, so a plain `docker build`
+    # reuses the host's layer cache and avoids buildx's docker-container
+    # driver + the gha cache exporter — neither works against this single-host
+    # act_runner, and there is no in-job daemon socket unless we mount it.
+    container:
+      image: docker.gitea.com/runner-images:ubuntu-latest
+      volumes:
+        - /var/run/docker.sock:/var/run/docker.sock
     outputs:
       image_tag: ${{ steps.meta.outputs.image_tag }}
       version: ${{ steps.meta.outputs.version }}
@@ -81,64 +101,53 @@ jobs:
           echo "image_tag=${GITHUB_SHA}" >> "$GITHUB_OUTPUT"
           echo "version=${version}" >> "$GITHUB_OUTPUT"
 
-      - uses: docker/setup-buildx-action@v3
-
-      - name: docker login
-        uses: docker/login-action@v3
-        with:
-          registry: ${{ secrets.REGISTRY_URL }}
-          username: ${{ secrets.REGISTRY_USERNAME }}
-          password: ${{ secrets.REGISTRY_PASSWORD }}
-
-      - name: Build & push backend
-        uses: docker/build-push-action@v5
-        with:
-          context: ./backend
-          push: true
-          tags: |
-            ${{ secrets.REGISTRY_URL }}/mangalord-backend:latest
-            ${{ secrets.REGISTRY_URL }}/mangalord-backend:${{ steps.meta.outputs.image_tag }}
-            ${{ secrets.REGISTRY_URL }}/mangalord-backend:${{ steps.meta.outputs.version }}
-          cache-from: type=gha,scope=backend
-          cache-to: type=gha,mode=max,scope=backend
-
-      - name: Build & push frontend
-        uses: docker/build-push-action@v5
-        with:
-          context: ./frontend
-          push: true
-          tags: |
-            ${{ secrets.REGISTRY_URL }}/mangalord-frontend:latest
-            ${{ secrets.REGISTRY_URL }}/mangalord-frontend:${{ steps.meta.outputs.image_tag }}
-            ${{ secrets.REGISTRY_URL }}/mangalord-frontend:${{ steps.meta.outputs.version }}
-          cache-from: type=gha,scope=frontend
-          cache-to: type=gha,mode=max,scope=frontend
+      - name: Build & push backend + frontend
+        env:
+          REGISTRY_URL: ${{ secrets.REGISTRY_URL }}
+          REGISTRY_USERNAME: ${{ secrets.REGISTRY_USERNAME }}
+          REGISTRY_PASSWORD: ${{ secrets.REGISTRY_PASSWORD }}
+          IMAGE_TAG: ${{ steps.meta.outputs.image_tag }}
+          VERSION: ${{ steps.meta.outputs.version }}
+        run: |
+          set -eu
+          echo "$REGISTRY_PASSWORD" | docker login "$REGISTRY_URL" -u "$REGISTRY_USERNAME" --password-stdin
+          for svc in backend frontend; do
+            img="$REGISTRY_URL/mangalord-$svc"
+            docker build -t "$img:$IMAGE_TAG" -t "$img:latest" -t "$img:$VERSION" "./$svc"
+            for tag in "$IMAGE_TAG" latest "$VERSION"; do docker push "$img:$tag"; done
+          done
+          docker logout "$REGISTRY_URL"
 
   deploy:
     runs-on: ubuntu-latest
     needs: build-and-push
+    if: github.event_name != 'pull_request'
+    # Single-host deploy: the runner lives on the same box as the stack, so we
+    # drive the host docker daemon directly (the job mounts the host docker
+    # socket) instead of SSHing out. The compose dir is bind-mounted at its
+    # REAL host path so compose's relative bind-mounts (./mangalord/...,
+    # ./Caddyfile) resolve; both paths must be in the runner's
+    # container.valid_volumes. The central compose references the images as
+    # registry.mc02.dev/mangalord-*:${MANGALORD_TAG:-latest}, so we only pull
+    # and recreate the two mangalord services at the freshly built SHA.
+    container:
+      image: docker:cli
+      volumes:
+        - /mnt/ssd/docker-data:/mnt/ssd/docker-data
+        - /var/run/docker.sock:/var/run/docker.sock
     steps:
-      - name: SSH deploy
-        uses: appleboy/ssh-action@v1.0.3
-        with:
-          host: ${{ secrets.SSH_HOST }}
-          username: ${{ secrets.SSH_USER }}
-          key: ${{ secrets.SSH_PRIVATE_KEY }}
-          port: ${{ secrets.SSH_PORT || 22 }}
-          envs: REGISTRY_URL,REGISTRY_USERNAME,REGISTRY_PASSWORD,IMAGE_TAG,DEPLOY_PATH
-          script_stop: true
-          script: |
-            set -euo pipefail
-            cd "$DEPLOY_PATH"
-            echo "$REGISTRY_PASSWORD" | docker login "$REGISTRY_URL" -u "$REGISTRY_USERNAME" --password-stdin
-            export REGISTRY_URL IMAGE_TAG
-            docker compose -f docker-compose.yml -f docker-compose.prod.yml pull
-            docker compose -f docker-compose.yml -f docker-compose.prod.yml up -d
-            docker image prune -f
-            docker logout "$REGISTRY_URL"
+      - name: Deploy to the local stack
+        working-directory: /mnt/ssd/docker-data
         env:
           REGISTRY_URL: ${{ secrets.REGISTRY_URL }}
           REGISTRY_USERNAME: ${{ secrets.REGISTRY_USERNAME }}
           REGISTRY_PASSWORD: ${{ secrets.REGISTRY_PASSWORD }}
           IMAGE_TAG: ${{ needs.build-and-push.outputs.image_tag }}
-          DEPLOY_PATH: ${{ vars.DEPLOY_PATH }}
+        run: |
+          set -eu
+          echo "$REGISTRY_PASSWORD" | docker login "$REGISTRY_URL" -u "$REGISTRY_USERNAME" --password-stdin
+          export MANGALORD_TAG="$IMAGE_TAG"
+          docker compose pull mangalord-backend mangalord-frontend
+          docker compose up -d mangalord-backend mangalord-frontend
+          docker image prune -f
+          docker logout "$REGISTRY_URL"

backend/Cargo.lock

@@ -1202,7 +1202,7 @@ dependencies = [
  "js-sys",
  "log",
  "wasm-bindgen",
- "windows-core",
+ "windows-core 0.62.2",
 ]
 
 [[package]]
@@ -1470,7 +1470,7 @@ checksum = "c41e0c4fef86961ac6d6f8a82609f55f31b05e4fce149ac5710e439df7619ba4"
 
 [[package]]
 name = "mangalord"
-version = "0.34.0"
+version = "0.52.0"
 dependencies = [
  "anyhow",
  "argon2",
@@ -1488,6 +1488,7 @@ dependencies = [
  "http-body-util",
  "infer",
  "mime",
+ "nix 0.29.0",
  "rand 0.8.6",
  "reqwest",
  "scraper",
@@ -1496,6 +1497,7 @@ dependencies = [
  "sha2",
  "sqlx",
  "subtle",
+ "sysinfo",
  "tempfile",
  "thiserror 1.0.69",
  "time",
@@ -1603,6 +1605,18 @@ version = "1.0.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "650eef8c711430f1a879fdd01d4745a7deea475becfb90269c06775983bbf086"
 
+[[package]]
+name = "nix"
+version = "0.29.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "71e2746dc3a24dd78b3cfcb7be93368c6de9963d30f43a6a73998a9cf4b17b46"
+dependencies = [
+ "bitflags",
+ "cfg-if",
+ "cfg_aliases",
+ "libc",
+]
+
 [[package]]
 name = "nix"
 version = "0.31.3"
@@ -1615,6 +1629,15 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "ntapi"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c3b335231dfd352ffb0f8017f3b6027a4917f7df785ea2143d8af2adc66980ae"
+dependencies = [
+ "winapi",
+]
+
 [[package]]
 name = "nu-ansi-term"
 version = "0.50.3"
@@ -1855,7 +1878,7 @@ checksum = "9cf20a545b305cf1da722b236b5155c9bb35f1d5ceb28c048bd96ca842f41b5b"
 dependencies = [
  "android_system_properties",
  "log",
- "nix",
+ "nix 0.31.3",
  "objc2",
  "objc2-foundation",
  "objc2-ui-kit",
@@ -2324,6 +2347,7 @@ dependencies = [
  "cookie",
  "cookie_store",
  "futures-core",
+ "futures-util",
  "http",
  "http-body",
  "http-body-util",
@@ -2343,12 +2367,14 @@ dependencies = [
  "sync_wrapper",
  "tokio",
  "tokio-rustls",
+ "tokio-util",
  "tower",
  "tower-http",
  "tower-service",
  "url",
  "wasm-bindgen",
  "wasm-bindgen-futures",
+ "wasm-streams",
  "web-sys",
  "webpki-roots",
 ]
@@ -2982,6 +3008,19 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "sysinfo"
+version = "0.32.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4c33cd241af0f2e9e3b5c32163b873b29956890b5342e6745b917ce9d490f4af"
+dependencies = [
+ "core-foundation-sys",
+ "libc",
+ "memchr",
+ "ntapi",
+ "windows",
+]
+
 [[package]]
 name = "tempfile"
 version = "3.27.0"
@@ -3527,6 +3566,19 @@ dependencies = [
  "wasmparser",
 ]
 
+[[package]]
+name = "wasm-streams"
+version = "0.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "15053d8d85c7eccdbefef60f06769760a563c7f0a9d6902a13d35c7800b0ad65"
+dependencies = [
+ "futures-util",
+ "js-sys",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+ "web-sys",
+]
+
 [[package]]
 name = "wasmparser"
 version = "0.244.0"
@@ -3590,19 +3642,74 @@ dependencies = [
  "wasite",
 ]
 
+[[package]]
+name = "winapi"
+version = "0.3.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5c839a674fcd7a98952e593242ea400abe93992746761e38641405d28b00f419"
+dependencies = [
+ "winapi-i686-pc-windows-gnu",
+ "winapi-x86_64-pc-windows-gnu",
+]
+
+[[package]]
+name = "winapi-i686-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
+
+[[package]]
+name = "winapi-x86_64-pc-windows-gnu"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
+
+[[package]]
+name = "windows"
+version = "0.57.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "12342cb4d8e3b046f3d80effd474a7a02447231330ef77d71daa6fbc40681143"
+dependencies = [
+ "windows-core 0.57.0",
+ "windows-targets 0.52.6",
+]
+
+[[package]]
+name = "windows-core"
+version = "0.57.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d2ed2439a290666cd67ecce2b0ffaad89c2a56b976b736e6ece670297897832d"
+dependencies = [
+ "windows-implement 0.57.0",
+ "windows-interface 0.57.0",
+ "windows-result 0.1.2",
+ "windows-targets 0.52.6",
+]
+
 [[package]]
 name = "windows-core"
 version = "0.62.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b8e83a14d34d0623b51dce9581199302a221863196a1dde71a7663a4c2be9deb"
 dependencies = [
- "windows-implement",
- "windows-interface",
+ "windows-implement 0.60.2",
+ "windows-interface 0.59.3",
  "windows-link",
- "windows-result",
+ "windows-result 0.4.1",
  "windows-strings",
 ]
 
+[[package]]
+name = "windows-implement"
+version = "0.57.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9107ddc059d5b6fbfbffdfa7a7fe3e22a226def0b2608f72e9d552763d3e1ad7"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "windows-implement"
 version = "0.60.2"
@@ -3614,6 +3721,17 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "windows-interface"
+version = "0.57.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "29bee4b38ea3cde66011baa44dba677c432a78593e202392d1e9070cf2a7fca7"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "windows-interface"
 version = "0.59.3"
@@ -3631,6 +3749,15 @@ version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f0805222e57f7521d6a62e36fa9163bc891acd422f971defe97d64e70d0a4fe5"
 
+[[package]]
+name = "windows-result"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5e383302e8ec8515204254685643de10811af0ed97ea37210dc26fb0032647f8"
+dependencies = [
+ "windows-targets 0.52.6",
+]
+
 [[package]]
 name = "windows-result"
 version = "0.4.1"

backend/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "mangalord"
-version = "0.34.0"
+version = "0.52.0"
 edition = "2021"
 default-run = "mangalord"
 
@@ -45,8 +45,10 @@ futures-core = "0.3"
 futures-util = "0.3"
 bytes = "1"
 chromiumoxide = { version = "0.7", features = ["tokio-runtime", "_fetcher-rusttls-tokio"], default-features = false }
+sysinfo = { version = "0.32", default-features = false, features = ["system"] }
+nix = { version = "0.29", features = ["fs"] }
 scraper = "0.20"
-reqwest = { version = "0.12", default-features = false, features = ["rustls-tls", "socks", "cookies"] }
+reqwest = { version = "0.12", default-features = false, features = ["rustls-tls", "socks", "cookies", "stream"] }
 
 [dev-dependencies]
 tempfile = "3"
@@ -55,3 +57,13 @@ http-body-util = "0.1"
 mime = "0.3"
 futures-util = "0.3"
 tokio = { version = "1", features = ["test-util"] }
+
+# Trim debug builds: keep line numbers in panics / backtraces but drop the
+# full DWARF info (variable-level inspection in gdb/lldb). With a sqlx +
+# axum + tokio dep tree the default ("full") leaves backend/target on the
+# order of tens of GiB; this typically cuts ~50–70% off that.
+[profile.dev]
+debug = "line-tables-only"
+
+[profile.test]
+debug = "line-tables-only"

backend/Dockerfile

@@ -10,7 +10,8 @@ RUN apt-get update \
 # exact crate versions CI tested. Without Cargo.lock + the flag, cargo
 # would silently resolve fresh on every image build.
 COPY Cargo.toml Cargo.lock ./
-RUN mkdir src && echo "fn main() {}" > src/main.rs && echo "" > src/lib.rs \
+RUN mkdir -p src/bin && echo "fn main() {}" > src/main.rs && echo "" > src/lib.rs \
+ && echo "fn main() {}" > src/bin/crawler.rs \
  && cargo build --locked --release \
  && rm -rf src
 
@@ -18,13 +19,68 @@ COPY src ./src
 COPY migrations ./migrations
 RUN touch src/main.rs src/lib.rs && cargo build --locked --release
 
-FROM debian:bookworm-slim
+FROM debian:trixie-slim
+# Runtime base must match the builder's Debian release: `rust:1-slim` tracks
+# trixie (glibc 2.41), so a bookworm runtime (glibc 2.36) can't run the
+# binary ("GLIBC_2.39 not found"). Keep these two in lockstep on bumps.
+# `curl` is for the container HEALTHCHECK; `ca-certificates` is for
+# outbound HTTPS (crawler covers/pages).
+#
+# INSTALL_CHROMIUM is an opt-in for deployments that can't use the
+# chromiumoxide fetcher path (notably Linux_arm64 / Raspberry Pi, where
+# the upstream snapshot bucket has no usable build). When `true`, adds
+# Debian's apt-packaged headless chromium plus a baseline font set —
+# pair with `CRAWLER_CHROMIUM_BINARY=/usr/bin/chromium-headless-shell`
+# at runtime so the launcher uses it. Default `false` keeps cloud/x86
+# images slim.
+#
+# Build the Pi image with:
+#   docker compose build --build-arg INSTALL_CHROMIUM=true backend
+ARG INSTALL_CHROMIUM=false
 RUN apt-get update \
- && apt-get install -y --no-install-recommends ca-certificates \
+ && apt-get install -y --no-install-recommends ca-certificates curl \
+ && if [ "$INSTALL_CHROMIUM" = "true" ]; then \
+      apt-get install -y --no-install-recommends chromium-headless-shell fonts-liberation; \
+    fi \
  && rm -rf /var/lib/apt/lists/*
+
+# Non-root runtime user. The API binary doesn't need any root
+# privilege; the crawler daemon's Chromium launcher uses --no-sandbox
+# precisely because user-namespace sandboxing is fragile, so dropping
+# privileges costs nothing operationally and shrinks the blast radius
+# of any RCE.
+ARG APP_UID=10001
+ARG APP_GID=10001
+RUN groupadd --system --gid ${APP_GID} app \
+ && useradd --system --uid ${APP_UID} --gid app --home-dir /home/app --create-home --shell /usr/sbin/nologin app
+
 WORKDIR /app
 COPY --from=builder /app/target/release/mangalord /usr/local/bin/mangalord
 COPY --from=builder /app/migrations /app/migrations
+
 ENV STORAGE_DIR=/var/lib/mangalord/storage
+# Pre-create the storage dir so the entrypoint doesn't need to
+# mkdir-as-root and so the named volume mount inherits the right
+# ownership.
+#
+# UPGRADE NOTE for operators: if you're moving from an older image
+# that ran as root, the existing `storage-data` volume has files owned
+# by UID 0 and the new UID-10001 user can't write them. Run once
+# before the upgrade:
+#   docker compose run --rm --user 0 backend \
+#     chown -R 10001:10001 /var/lib/mangalord/storage
+# (Postgres is unaffected — that image's `postgres` user UID hasn't
+# changed.)
+RUN mkdir -p ${STORAGE_DIR} \
+ && chown -R app:app ${STORAGE_DIR} /app /home/app
+
+USER app
 EXPOSE 8080
+
+# `--start-period` is generous because first boot runs sqlx::migrate
+# against postgres which can take a few seconds; subsequent restarts
+# are sub-second.
+HEALTHCHECK --interval=30s --timeout=5s --start-period=20s --retries=3 \
+  CMD curl -fsS http://localhost:8080/api/v1/health > /dev/null || exit 1
+
 CMD ["mangalord"]

backend/migrations/0016_crawler_jobs_drop_failed_state.sql

@@ -0,0 +1,15 @@
+-- The original 0012 partial index covers `state IN ('pending','failed')`,
+-- but `ack_failed` in src/crawler/jobs.rs only writes `dead` or
+-- `pending` — `failed` is never set. The index branch on `failed`
+-- never matches any row, so it's dead weight on every write.
+--
+-- Drop and recreate the index without the dead branch. The CHECK
+-- constraint on `state` still allows `'failed'` so a future migration
+-- can adopt that terminal-but-retryable state without a second
+-- schema change.
+
+DROP INDEX IF EXISTS crawler_jobs_ready_idx;
+
+CREATE INDEX crawler_jobs_ready_idx
+    ON crawler_jobs (scheduled_at)
+    WHERE state = 'pending';

backend/migrations/0017_chapter_sources_per_manga.sql

@@ -0,0 +1,20 @@
+-- chapter_sources: drop the global (source_id, source_chapter_key) PK
+-- and rekey on (source_id, chapter_id).
+--
+-- The old PK assumed chapter slugs are unique per source. Sources whose
+-- chapter naming is per-manga (chapter-1, chapter-2, ...) instead of per-
+-- catalog (br_chapter-379272 with a global counter) would collide on the
+-- second manga: the INSERT would conflict on (source_id, "chapter-1") and
+-- the lookup would attribute the row to the first manga's chapter_id.
+--
+-- The new key is the natural identity of a source attachment: "this source
+-- has this chapter". An (source_id, source_chapter_key) index preserves
+-- the lookup path (find existing source row by source's identifier) but
+-- no longer enforces uniqueness — the application combines it with the
+-- chapters table's manga_id to scope the lookup per-manga.
+
+ALTER TABLE chapter_sources DROP CONSTRAINT chapter_sources_pkey;
+ALTER TABLE chapter_sources ADD PRIMARY KEY (source_id, chapter_id);
+
+CREATE INDEX chapter_sources_source_key_idx
+    ON chapter_sources (source_id, source_chapter_key);

backend/migrations/0018_admin_role.sql

@@ -0,0 +1,5 @@
+-- Admin role flag on users. Booted from ADMIN_USERNAME / ADMIN_PASSWORD env at
+-- startup (see app::build). Demotion is instant: the RequireAdmin extractor
+-- re-reads the user row every request, so flipping this column takes effect on
+-- the next call without a session purge.
+ALTER TABLE users ADD COLUMN is_admin BOOLEAN NOT NULL DEFAULT false;

backend/migrations/0019_admin_audit.sql

@@ -0,0 +1,20 @@
+-- Admin audit log. Written from inside the same transaction as the action
+-- it records, so a failed COMMIT also rolls back the audit row — the log
+-- never claims an action happened that didn't.
+--
+-- `actor_user_id` is ON DELETE SET NULL so audit rows outlive a deleted
+-- admin (the answer to "who promoted Bob to admin?" survives even after
+-- Alice's account is removed). `target_id` is intentionally not a FK
+-- because future audit kinds may target non-user rows (manga, source,
+-- etc.) and a single typed FK can't express that.
+CREATE TABLE admin_audit (
+    id            uuid PRIMARY KEY DEFAULT gen_random_uuid(),
+    actor_user_id uuid REFERENCES users(id) ON DELETE SET NULL,
+    action        text NOT NULL,
+    target_kind   text NOT NULL,
+    target_id     uuid,
+    payload       jsonb NOT NULL DEFAULT '{}'::jsonb,
+    at            timestamptz NOT NULL DEFAULT now()
+);
+
+CREATE INDEX admin_audit_at_idx ON admin_audit (at DESC);

backend/migrations/0020_admin_jobs_payload_index.sql

@@ -0,0 +1,14 @@
+-- Per-manga sync-state derivation joins crawler_jobs to manga_sources via
+-- (payload->>'source_id', payload->>'source_manga_key') for the
+-- `sync_manga` job kind (whose payload doesn't carry a manga_id directly).
+-- Without this index the join falls back to a seqscan of crawler_jobs on
+-- every admin manga listing — a noticeable cost as the job table grows
+-- with the daily metadata pass.
+--
+-- Partial on `state IN ('pending','running')` so it covers only in-flight
+-- jobs (the bulk of the table is done/dead and irrelevant to "is this
+-- manga being synced right now").
+CREATE INDEX crawler_jobs_sync_manga_key_idx
+    ON crawler_jobs ((payload->>'source_manga_key'))
+ WHERE state IN ('pending', 'running')
+   AND payload->>'kind' = 'sync_manga';

backend/migrations/0021_chapter_source_index.sql

@@ -0,0 +1,18 @@
+-- Capture each chapter's position in the source site's chapter list so
+-- the user-facing list can preserve site order: variants of the same
+-- chapter number (e.g. "Ch.14 : PH" next to "Ch.14 : Official") stay
+-- adjacent, and non-numeric entries like "notice. : Officials" land
+-- where the site placed them rather than clustering at the top under
+-- number = 0.
+--
+-- Lower source_index = closer to the top of the source DOM = newer
+-- chapter on this site (it renders newest-first). The list query
+-- reverses this with ORDER BY source_index DESC so the oldest chapter
+-- appears first in our UI.
+--
+-- NULL is the sentinel for user-uploaded chapters (no source row) and
+-- for crawled rows that pre-date this migration. The list query keeps
+-- the existing (number, created_at) tiebreak via NULLS LAST so those
+-- fall through to the prior behaviour until the next crawler tick
+-- populates the column.
+ALTER TABLE chapters ADD COLUMN source_index INTEGER;

backend/src/api/admin/mangas.rs

@@ -0,0 +1,110 @@
+//! Admin manga/chapter overview with derived sync state.
+//!
+//! Sync state comes from `repo::admin_view`, which joins the manga /
+//! chapter tables with the crawler signals at query time — there is no
+//! persisted sync_state column. See [`repo::admin_view`] for the
+//! derivation priority order.
+
+use axum::extract::{Path, Query, State};
+use axum::routing::get;
+use axum::{Json, Router};
+use serde::Deserialize;
+use uuid::Uuid;
+
+use crate::api::pagination::PagedResponse;
+use crate::app::AppState;
+use crate::auth::extractor::RequireAdmin;
+use crate::domain::MangaSyncState;
+use crate::error::{AppError, AppResult};
+use crate::repo;
+use crate::repo::admin_view::{AdminChapterRow, AdminMangaRow};
+
+pub fn routes() -> Router<AppState> {
+    Router::new()
+        .route("/admin/mangas", get(list_mangas))
+        .route("/admin/mangas/:id/chapters", get(list_chapters))
+}
+
+#[derive(Debug, Deserialize, Default)]
+pub struct ListChaptersParams {
+    #[serde(default = "default_chapter_limit")]
+    pub limit: i64,
+    #[serde(default)]
+    pub offset: i64,
+}
+
+fn default_chapter_limit() -> i64 {
+    200
+}
+
+#[derive(Debug, Deserialize, Default)]
+pub struct ListMangasParams {
+    #[serde(default)]
+    pub search: Option<String>,
+    /// `in_progress` | `dropped` | `synced`. Unrecognised values are a 400.
+    #[serde(default)]
+    pub sync_state: Option<String>,
+    #[serde(default = "default_limit")]
+    pub limit: i64,
+    #[serde(default)]
+    pub offset: i64,
+}
+
+fn default_limit() -> i64 {
+    50
+}
+
+async fn list_mangas(
+    State(state): State<AppState>,
+    _admin: RequireAdmin,
+    Query(params): Query<ListMangasParams>,
+) -> AppResult<Json<PagedResponse<AdminMangaRow>>> {
+    let limit = params.limit.clamp(1, 200);
+    let offset = params.offset.max(0);
+
+    let sync_state = match params.sync_state.as_deref() {
+        None | Some("") => None,
+        Some("in_progress") => Some(MangaSyncState::InProgress),
+        Some("dropped") => Some(MangaSyncState::Dropped),
+        Some("synced") => Some(MangaSyncState::Synced),
+        Some(other) => {
+            return Err(AppError::InvalidInput(format!(
+                "sync_state must be one of in_progress|dropped|synced (got {other:?})"
+            )));
+        }
+    };
+
+    let q = repo::admin_view::ListAdminMangasQuery {
+        search: params.search.filter(|s| !s.trim().is_empty()),
+        sync_state,
+        limit,
+        offset,
+    };
+    let (items, total) = repo::admin_view::list_mangas_with_sync_state(&state.db, &q).await?;
+    Ok(Json(PagedResponse::with_total(items, limit, offset, total)))
+}
+
+async fn list_chapters(
+    State(state): State<AppState>,
+    _admin: RequireAdmin,
+    Path(manga_id): Path<Uuid>,
+    Query(params): Query<ListChaptersParams>,
+) -> AppResult<Json<PagedResponse<AdminChapterRow>>> {
+    // Explicit existence check so a typo / deleted manga returns 404
+    // rather than a misleading "no chapters" 200.
+    if !repo::manga::exists(&state.db, manga_id).await? {
+        return Err(AppError::NotFound);
+    }
+    // Cap at 500 to bound the per-row scalar-subquery cost on
+    // long-runners with thousands of chapters; default 200 covers
+    // typical browsing without paging round-trips.
+    let limit = params.limit.clamp(1, 500);
+    let offset = params.offset.max(0);
+    let q = repo::admin_view::ListAdminChaptersQuery {
+        manga_id,
+        limit,
+        offset,
+    };
+    let (items, total) = repo::admin_view::list_chapters_with_sync_state(&state.db, &q).await?;
+    Ok(Json(PagedResponse::with_total(items, limit, offset, total)))
+}

backend/src/api/admin/mod.rs

@@ -0,0 +1,22 @@
+//! Admin-only endpoints. Mounted under `/api/v1/admin/*` by
+//! `crate::api::routes`. Every handler in this subtree is guarded by
+//! `RequireAdmin`, which only accepts session-cookie authentication —
+//! bot/API tokens cannot reach admin routes (see
+//! `crate::auth::extractor::RequireAdmin`).
+
+pub mod mangas;
+pub mod resync;
+pub mod system;
+pub mod users;
+
+use axum::Router;
+
+use crate::app::AppState;
+
+pub fn routes() -> Router<AppState> {
+    Router::new()
+        .merge(users::routes())
+        .merge(mangas::routes())
+        .merge(resync::routes())
+        .merge(system::routes())
+}

backend/src/api/admin/resync.rs

@@ -0,0 +1,176 @@
+//! Admin-triggered force resync of a single manga's metadata + cover,
+//! or a single chapter's content.
+//!
+//! Both endpoints are admin-only (`RequireAdmin`, cookie-only) and run
+//! synchronously with the request — the response carries the refreshed
+//! resource so the UI can swap it in without a follow-up GET. The work
+//! itself is delegated to [`ResyncService`] (set on AppState by
+//! `app::build` when the crawler daemon is enabled); when the daemon
+//! is disabled, both handlers return 503.
+
+use axum::extract::{Path, State};
+use axum::routing::post;
+use axum::{Json, Router};
+use serde::Serialize;
+use serde_json::json;
+use uuid::Uuid;
+
+use crate::app::AppState;
+use crate::auth::extractor::RequireAdmin;
+use crate::crawler::resync::{ChapterResyncOutcome, ResyncError};
+use crate::domain::manga::MangaDetail;
+use crate::domain::Chapter;
+use crate::error::{AppError, AppResult};
+use crate::repo;
+use crate::repo::crawler::UpsertStatus;
+
+pub fn routes() -> Router<AppState> {
+    Router::new()
+        .route("/admin/mangas/:id/resync", post(resync_manga))
+        .route("/admin/chapters/:id/resync", post(resync_chapter))
+}
+
+#[derive(Debug, Serialize)]
+pub struct MangaResyncResponse {
+    pub manga: MangaDetail,
+    /// `"new" | "updated" | "unchanged"` — mirrors [`UpsertStatus`].
+    pub metadata_status: &'static str,
+    pub cover_fetched: bool,
+}
+
+#[derive(Debug, Serialize)]
+pub struct ChapterResyncResponse {
+    pub chapter: Chapter,
+    /// `"fetched" | "skipped"` — whether new pages landed or the
+    /// service short-circuited (e.g. chapter already had pages and the
+    /// session was lost so force was downgraded).
+    pub outcome: &'static str,
+    /// Page count when `outcome == "fetched"`. `None` for `skipped`.
+    pub pages: Option<usize>,
+}
+
+async fn resync_manga(
+    State(state): State<AppState>,
+    admin: RequireAdmin,
+    Path(manga_id): Path<Uuid>,
+) -> AppResult<Json<MangaResyncResponse>> {
+    if !repo::manga::exists(&state.db, manga_id).await? {
+        return Err(AppError::NotFound);
+    }
+    let resync = state
+        .resync
+        .as_ref()
+        .ok_or_else(|| AppError::ServiceUnavailable(
+            "crawler daemon is disabled; force resync unavailable".into(),
+        ))?;
+
+    let outcome = resync.resync_manga(manga_id).await.map_err(map_resync_err)?;
+
+    // Audit the action with the actor + the resync outcome so an
+    // operator-of-operators can answer "who refetched this manga, and
+    // did the cover land?" from the log alone.
+    repo::admin_audit::insert(
+        &state.db,
+        admin.0.id,
+        "manga_resync",
+        "manga",
+        Some(manga_id),
+        json!({
+            "metadata_status": status_str(outcome.metadata_status),
+            "cover_fetched": outcome.cover_fetched,
+        }),
+    )
+    .await?;
+
+    let manga = repo::manga::get_detail(&state.db, manga_id).await?;
+    Ok(Json(MangaResyncResponse {
+        manga,
+        metadata_status: status_str(outcome.metadata_status),
+        cover_fetched: outcome.cover_fetched,
+    }))
+}
+
+async fn resync_chapter(
+    State(state): State<AppState>,
+    admin: RequireAdmin,
+    Path(chapter_id): Path<Uuid>,
+) -> AppResult<Json<ChapterResyncResponse>> {
+    let resync = state
+        .resync
+        .as_ref()
+        .ok_or_else(|| AppError::ServiceUnavailable(
+            "crawler daemon is disabled; force resync unavailable".into(),
+        ))?;
+
+    // Look up the manga the chapter belongs to so we can return the
+    // refreshed chapter row in the response and 404 for unknown ids.
+    let manga_id: Option<Uuid> =
+        sqlx::query_scalar("SELECT manga_id FROM chapters WHERE id = $1")
+            .bind(chapter_id)
+            .fetch_optional(&state.db)
+            .await?;
+    let Some(manga_id) = manga_id else {
+        return Err(AppError::NotFound);
+    };
+
+    let outcome = resync
+        .resync_chapter(chapter_id)
+        .await
+        .map_err(map_resync_err)?;
+
+    let (outcome_str, pages) = match &outcome {
+        ChapterResyncOutcome::Fetched { pages, .. } => ("fetched", Some(*pages)),
+        ChapterResyncOutcome::Skipped { .. } => ("skipped", None),
+    };
+
+    repo::admin_audit::insert(
+        &state.db,
+        admin.0.id,
+        "chapter_resync",
+        "chapter",
+        Some(chapter_id),
+        json!({
+            "outcome": outcome_str,
+            "pages": pages,
+        }),
+    )
+    .await?;
+
+    let chapter = repo::chapter::find_by_id_in_manga(&state.db, manga_id, chapter_id)
+        .await?
+        .ok_or(AppError::NotFound)?;
+    Ok(Json(ChapterResyncResponse {
+        chapter,
+        outcome: outcome_str,
+        pages,
+    }))
+}
+
+fn status_str(s: UpsertStatus) -> &'static str {
+    match s {
+        UpsertStatus::New => "new",
+        UpsertStatus::Updated => "updated",
+        UpsertStatus::Unchanged => "unchanged",
+    }
+}
+
+/// Map [`ResyncError`] (and the anyhow envelopes wrapping it) onto the
+/// right [`AppError`]. Anything else surfaces as a generic 500 via the
+/// `Other` arm — the operator sees the underlying anyhow chain in
+/// server logs, the client sees a clean envelope.
+fn map_resync_err(err: anyhow::Error) -> AppError {
+    if let Some(rerr) = err.downcast_ref::<ResyncError>() {
+        match rerr {
+            ResyncError::NoMangaSource => AppError::ValidationFailed {
+                message: "manga has no live crawler source — cannot resync".into(),
+                details: json!({ "manga": "no_source" }),
+            },
+            ResyncError::NoChapterSource => AppError::ValidationFailed {
+                message: "chapter has no live crawler source — cannot resync".into(),
+                details: json!({ "chapter": "no_source" }),
+            },
+        }
+    } else {
+        AppError::Other(err)
+    }
+}

backend/src/api/admin/system.rs

@@ -0,0 +1,163 @@
+//! System metrics for the admin dashboard.
+//!
+//! Disk is `statvfs(storage_dir)` so the number reflects the volume the
+//! app actually writes to (not the root filesystem of the host). When the
+//! storage backend doesn't expose a local path (e.g. a future S3 impl)
+//! the disk fields are `null` rather than fabricated.
+//!
+//! Memory and CPU come from `sysinfo`. CPU requires two refreshes with
+//! at least 200ms between them to compute a meaningful delta; the
+//! handler eats the 250ms wall-clock cost on each request. Admin
+//! traffic is low-volume so a background cache isn't worth the moving
+//! parts yet — revisit if polling becomes frequent.
+
+use std::path::Path;
+use std::time::Duration;
+
+use axum::extract::State;
+use axum::routing::get;
+use axum::{Json, Router};
+use serde::Serialize;
+use sysinfo::{CpuRefreshKind, MemoryRefreshKind, RefreshKind, System};
+
+use crate::app::AppState;
+use crate::auth::extractor::RequireAdmin;
+use crate::error::AppResult;
+
+const ALERT_THRESHOLD_PERCENT: f64 = 90.0;
+
+pub fn routes() -> Router<AppState> {
+    Router::new().route("/admin/system", get(system))
+}
+
+#[derive(Debug, Serialize)]
+pub struct SystemStats {
+    pub disk: Option<DiskStats>,
+    pub memory: MemoryStats,
+    pub cpu: CpuStats,
+    pub alerts: Vec<Alert>,
+}
+
+#[derive(Debug, Serialize)]
+pub struct DiskStats {
+    pub total_bytes: u64,
+    pub used_bytes: u64,
+    pub free_bytes: u64,
+    pub percent_used: f64,
+}
+
+#[derive(Debug, Serialize)]
+pub struct MemoryStats {
+    pub total_bytes: u64,
+    pub used_bytes: u64,
+    pub percent_used: f64,
+}
+
+#[derive(Debug, Serialize)]
+pub struct CpuStats {
+    pub percent_used: f64,
+}
+
+#[derive(Debug, Serialize)]
+pub struct Alert {
+    pub level: AlertLevel,
+    pub message: String,
+}
+
+#[derive(Debug, Serialize, Clone, Copy)]
+#[serde(rename_all = "snake_case")]
+pub enum AlertLevel {
+    Warning,
+}
+
+async fn system(
+    State(state): State<AppState>,
+    _admin: RequireAdmin,
+) -> AppResult<Json<SystemStats>> {
+    let disk = state.storage.local_root().and_then(disk_stats_for);
+    let (memory, cpu) = memory_and_cpu().await;
+    let mut alerts = Vec::new();
+    if let Some(d) = &disk {
+        if d.percent_used >= ALERT_THRESHOLD_PERCENT {
+            alerts.push(Alert {
+                level: AlertLevel::Warning,
+                message: format!(
+                    "disk near full ({:.0}% used)",
+                    d.percent_used
+                ),
+            });
+        }
+    }
+    if memory.percent_used >= ALERT_THRESHOLD_PERCENT {
+        alerts.push(Alert {
+            level: AlertLevel::Warning,
+            message: format!(
+                "memory near full ({:.0}% used)",
+                memory.percent_used
+            ),
+        });
+    }
+    Ok(Json(SystemStats {
+        disk,
+        memory,
+        cpu,
+        alerts,
+    }))
+}
+
+fn disk_stats_for(root: &Path) -> Option<DiskStats> {
+    let s = nix::sys::statvfs::statvfs(root).ok()?;
+    // statvfs reports `f_frsize * f_blocks` for total bytes. `f_bavail`
+    // is "free to non-root callers" which is what an operator actually
+    // cares about — `f_bfree` includes blocks reserved for root.
+    let block = s.fragment_size();
+    let total = block * s.blocks();
+    let avail = block * s.blocks_available();
+    let used = total.saturating_sub(avail);
+    let percent_used = if total > 0 {
+        (used as f64) * 100.0 / (total as f64)
+    } else {
+        0.0
+    };
+    Some(DiskStats {
+        total_bytes: total,
+        used_bytes: used,
+        free_bytes: avail,
+        percent_used,
+    })
+}
+
+async fn memory_and_cpu() -> (MemoryStats, CpuStats) {
+    // sysinfo's CPU sampling needs two refreshes with a delay between
+    // them — the first seeds the delta counters, the second measures.
+    // We do this once per request; admin traffic is low enough that the
+    // 250ms cost is invisible.
+    let mut sys = System::new_with_specifics(
+        RefreshKind::new()
+            .with_cpu(CpuRefreshKind::everything())
+            .with_memory(MemoryRefreshKind::everything()),
+    );
+    sys.refresh_cpu_all();
+    // Yield the runtime instead of blocking it for the gap.
+    tokio::time::sleep(Duration::from_millis(250)).await;
+    sys.refresh_cpu_all();
+    sys.refresh_memory();
+
+    let total = sys.total_memory();
+    let used = sys.used_memory();
+    let mem_pct = if total > 0 {
+        (used as f64) * 100.0 / (total as f64)
+    } else {
+        0.0
+    };
+    let memory = MemoryStats {
+        total_bytes: total,
+        used_bytes: used,
+        percent_used: mem_pct,
+    };
+
+    let cpu = CpuStats {
+        percent_used: sys.global_cpu_usage() as f64,
+    };
+    (memory, cpu)
+}

backend/src/api/admin/users.rs

@@ -0,0 +1,128 @@
+//! Admin user management: list, delete, promote/demote.
+//!
+//! All handlers are gated by `RequireAdmin` and rely on
+//! `repo::user::admin_safe_*` for self-protection and the last-admin
+//! invariant. Audit rows are written inside the same DB transaction as
+//! the action they record.
+
+use axum::extract::{Path, Query, State};
+use axum::http::StatusCode;
+use axum::routing::{delete, get};
+use axum::{Json, Router};
+use serde::Deserialize;
+use uuid::Uuid;
+
+use crate::api::auth::{validate_password, validate_username};
+use crate::api::pagination::PagedResponse;
+use crate::app::AppState;
+use crate::auth::extractor::RequireAdmin;
+use crate::auth::password::hash_password;
+use crate::domain::User;
+use crate::error::{AppError, AppResult};
+use crate::repo;
+
+pub fn routes() -> Router<AppState> {
+    Router::new()
+        .route("/admin/users", get(list_users).post(create_user))
+        .route(
+            "/admin/users/:id",
+            delete(delete_user).patch(update_user),
+        )
+}
+
+#[derive(Debug, Deserialize, Default)]
+pub struct ListUsersParams {
+    #[serde(default)]
+    pub search: Option<String>,
+    #[serde(default = "default_limit")]
+    pub limit: i64,
+    #[serde(default)]
+    pub offset: i64,
+}
+
+fn default_limit() -> i64 {
+    50
+}
+
+async fn list_users(
+    State(state): State<AppState>,
+    _admin: RequireAdmin,
+    Query(params): Query<ListUsersParams>,
+) -> AppResult<Json<PagedResponse<User>>> {
+    let limit = params.limit.clamp(1, 200);
+    let offset = params.offset.max(0);
+    let (items, total) = repo::user::list_with_total(
+        &state.db,
+        &repo::user::ListUsersQuery {
+            search: params.search.filter(|s| !s.trim().is_empty()),
+            limit,
+            offset,
+        },
+    )
+    .await?;
+    Ok(Json(PagedResponse::with_total(items, limit, offset, total)))
+}
+
+#[derive(Debug, Deserialize)]
+pub struct UpdateUserInput {
+    pub is_admin: Option<bool>,
+}
+
+async fn update_user(
+    State(state): State<AppState>,
+    RequireAdmin(actor): RequireAdmin,
+    Path(id): Path<Uuid>,
+    Json(input): Json<UpdateUserInput>,
+) -> AppResult<Json<User>> {
+    let Some(is_admin) = input.is_admin else {
+        return Err(AppError::InvalidInput(
+            "no updatable fields supplied".into(),
+        ));
+    };
+    let updated =
+        repo::user::admin_safe_set_is_admin(&state.db, actor.id, id, is_admin).await?;
+    Ok(Json(updated))
+}
+
+async fn delete_user(
+    State(state): State<AppState>,
+    RequireAdmin(actor): RequireAdmin,
+    Path(id): Path<Uuid>,
+) -> AppResult<StatusCode> {
+    repo::user::admin_safe_delete(&state.db, actor.id, id).await?;
+    Ok(StatusCode::NO_CONTENT)
+}
+
+#[derive(Debug, Deserialize)]
+pub struct CreateUserInput {
+    pub username: String,
+    pub password: String,
+    /// Defaults to false; admins may mint other admins in a single
+    /// call. Doing it as one POST avoids a second audit row for the
+    /// common "invite a co-admin" flow.
+    #[serde(default)]
+    pub is_admin: bool,
+}
+
+async fn create_user(
+    State(state): State<AppState>,
+    RequireAdmin(actor): RequireAdmin,
+    Json(input): Json<CreateUserInput>,
+) -> AppResult<(StatusCode, Json<User>)> {
+    let username = input.username.trim();
+    // Reuse the canonical self-register validators so the admin-create
+    // path can never produce a username that self-register would
+    // reject (and vice versa).
+    validate_username(username)?;
+    validate_password(&input.password)?;
+    let pwhash = hash_password(&input.password)?;
+    let user = repo::user::admin_create_user(
+        &state.db,
+        actor.id,
+        username,
+        &pwhash,
+        input.is_admin,
+    )
+    .await?;
+    Ok((StatusCode::CREATED, Json(user)))
+}

backend/src/api/auth.rs

@@ -4,6 +4,8 @@
 //! expire naturally rather than being explicitly invalidated, so other
 //! devices keep their existing logins).
 
+use std::sync::OnceLock;
+
 use axum::extract::{Path, State};
 use axum::http::StatusCode;
 use axum::response::IntoResponse;
@@ -26,6 +28,7 @@ use crate::repo;
 
 pub fn routes() -> Router<AppState> {
     Router::new()
+        .route("/auth/config", get(auth_config))
         .route("/auth/register", post(register))
         .route("/auth/login", post(login))
         .route("/auth/logout", post(logout))
@@ -39,6 +42,25 @@ pub fn routes() -> Router<AppState> {
         .route("/auth/tokens/:id", delete(delete_token))
 }
 
+/// Public, unauthenticated. Exposes anonymous-relevant auth policy so
+/// the frontend can render its login / register affordances correctly
+/// without a probe request that would conflate "disabled" with
+/// "rate-limited". `self_register_enabled` is the *effective* value
+/// (`allow_self_register && !private_mode`), so a private-mode
+/// instance reports `false` even if the raw flag is on.
+#[derive(Debug, Serialize)]
+pub struct AuthConfigResponse {
+    pub self_register_enabled: bool,
+    pub private_mode: bool,
+}
+
+async fn auth_config(State(state): State<AppState>) -> Json<AuthConfigResponse> {
+    Json(AuthConfigResponse {
+        self_register_enabled: state.auth.allow_self_register && !state.auth.private_mode,
+        private_mode: state.auth.private_mode,
+    })
+}
+
 #[derive(Debug, Deserialize)]
 pub struct Credentials {
     pub username: String,
@@ -80,6 +102,17 @@ async fn register(
     jar: CookieJar,
     Json(input): Json<Credentials>,
 ) -> AppResult<impl IntoResponse> {
+    // Rate limit before the disabled check so an operator who flips
+    // the toggle can't be probed for the toggle state via timing —
+    // disabled and enabled paths both consume a token, and disabled
+    // returns 403 instead of running argon2.
+    check_auth_rate_limit(&state, "register")?;
+    // Private mode force-blocks self-registration regardless of
+    // ALLOW_SELF_REGISTER — operators of locked-down instances mint
+    // accounts via `POST /admin/users` instead.
+    if !state.auth.allow_self_register || state.auth.private_mode {
+        return Err(AppError::Forbidden);
+    }
     let username = input.username.trim();
     validate_username(username)?;
     validate_password(&input.password)?;
@@ -95,6 +128,7 @@ async fn login(
     jar: CookieJar,
     Json(input): Json<Credentials>,
 ) -> AppResult<impl IntoResponse> {
+    check_auth_rate_limit(&state, "login")?;
     let username = input.username.trim();
     if username.is_empty() || input.password.is_empty() {
         return Err(AppError::InvalidInput(
@@ -102,9 +136,15 @@ async fn login(
         ));
     }
 
-    let user = repo::user::find_by_username(&state.db, username)
-        .await?
-        .ok_or(AppError::Unauthenticated)?;
+    let user = repo::user::find_by_username(&state.db, username).await?;
+    let Some(user) = user else {
+        // No such user. Run argon2 against a stable dummy hash so the
+        // response time matches the wrong-password branch — otherwise
+        // an attacker can enumerate usernames by timing the no-user
+        // 401 against the wrong-password 401.
+        let _ = verify_password(&input.password, dummy_password_hash());
+        return Err(AppError::Unauthenticated);
+    };
     if !verify_password(&input.password, &user.password_hash) {
         return Err(AppError::Unauthenticated);
     }
@@ -113,6 +153,21 @@ async fn login(
     Ok((StatusCode::OK, jar, Json(AuthResponse { user })))
 }
 
+/// Lazily-computed argon2 hash used to equalise login response time
+/// across the "no such user" and "wrong password" branches. Computing
+/// it once (on the first login of the process) is enough — the hash is
+/// never compared against a real password, only used to force argon2
+/// to do the same amount of work it would for a real verify.
+fn dummy_password_hash() -> &'static str {
+    static DUMMY: OnceLock<String> = OnceLock::new();
+    DUMMY
+        .get_or_init(|| {
+            crate::auth::password::hash_password("login-timing-equaliser")
+                .expect("hash_password on a fixed input cannot fail")
+        })
+        .as_str()
+}
+
 async fn logout(
     State(state): State<AppState>,
     jar: CookieJar,
@@ -149,6 +204,7 @@ async fn change_password(
     jar: CookieJar,
     Json(input): Json<ChangePassword>,
 ) -> AppResult<impl IntoResponse> {
+    check_auth_rate_limit(&state, "change_password")?;
     if !verify_password(&input.current_password, &user.password_hash) {
         return Err(AppError::Unauthenticated);
     }
@@ -230,8 +286,24 @@ async fn create_token(
     Json(input): Json<CreateTokenInput>,
 ) -> AppResult<impl IntoResponse> {
     let name = input.name.trim();
+    // Both arms use `ValidationFailed` (422 with field details) to
+    // match the structured-error shape `attach_tag` returns for the
+    // same kind of free-form-identifier validation. The other
+    // /auth/* handlers in this file use `InvalidInput` (400); the
+    // divergence is pre-existing and would warrant a project-wide
+    // pass to flip them all if the client side wants uniform per-
+    // field error rendering.
     if name.is_empty() {
-        return Err(AppError::InvalidInput("token name is required".into()));
+        return Err(AppError::ValidationFailed {
+            message: "token name is required".into(),
+            details: serde_json::json!({ "name": "required" }),
+        });
+    }
+    if name.chars().count() > 64 {
+        return Err(AppError::ValidationFailed {
+            message: "token name too long".into(),
+            details: serde_json::json!({ "name": "max 64 characters" }),
+        });
     }
     let (raw, hash) = generate_token();
     let token = repo::api_token::create(&state.db, user.id, name, &hash).await?;
@@ -267,6 +339,18 @@ async fn start_session(
     Ok(jar.add(build_session_cookie(raw, &state.auth)))
 }
 
+// CSRF posture: `SameSite=Lax` is the project's primary CSRF defense.
+// Browsers refuse to attach this cookie to cross-site POST / PATCH /
+// DELETE requests, which covers every state-changing endpoint (auth
+// mutations, uploads, bookmarks, collections, admin user management,
+// etc. — all JSON over POST/PATCH/DELETE). Lax DOES still attach the
+// cookie on top-level cross-site GETs, so this defense breaks the
+// instant anyone adds a state-changing GET. If you reach for one,
+// switch to `SameSite=Strict` here AND add an explicit CSRF-token
+// check on the new endpoint. The Bearer-token branch in the
+// extractor is unaffected (bots authenticate with the token header,
+// not the cookie) and admin routes reject Bearer entirely — see
+// `auth::extractor::RequireAdmin`.
 fn build_session_cookie(raw: String, cfg: &AuthConfig) -> Cookie<'static> {
     let mut builder = Cookie::build((SESSION_COOKIE_NAME, raw))
         .http_only(true)
@@ -293,7 +377,38 @@ fn build_expired_cookie(cfg: &AuthConfig) -> Cookie<'static> {
     builder.build()
 }
 
-fn validate_username(u: &str) -> AppResult<()> {
+/// Consume one token from the shared auth rate limiter. Called at the
+/// start of `register`, `login`, and `change_password` so credential
+/// stuffing / spraying / username-probe loops are throttled by the
+/// configured budget (default 5/sec with a 10-request burst).
+///
+/// All three endpoints share one bucket — they all expose the same
+/// argon2-verify-or-create work and the same enumeration channels, so
+/// any one of them in a tight loop should trip the limit. `endpoint`
+/// is included in the rate-limit-hit log line so operators can tell
+/// which endpoint is being probed.
+fn check_auth_rate_limit(state: &AppState, endpoint: &'static str) -> AppResult<()> {
+    use crate::auth::rate_limit::AcquireResult;
+    match state.auth_limiter.try_acquire() {
+        AcquireResult::Allowed => Ok(()),
+        AcquireResult::Denied { retry_after_secs } => {
+            tracing::warn!(
+                endpoint,
+                retry_after_secs,
+                "auth rate limit hit; returning 429"
+            );
+            Err(AppError::TooManyRequests {
+                retry_after_secs: Some(retry_after_secs),
+            })
+        }
+    }
+}
+
+// Exposed pub(crate) so the admin user-create handler can apply the
+// same rules as self-registration. Keeping the lone canonical
+// implementation here avoids the two paths drifting on min length /
+// allowed character set.
+pub(crate) fn validate_username(u: &str) -> AppResult<()> {
     if u.is_empty() {
         return Err(AppError::InvalidInput("username is required".into()));
     }
@@ -310,7 +425,7 @@ fn validate_username(u: &str) -> AppResult<()> {
     Ok(())
 }
 
-fn validate_password(p: &str) -> AppResult<()> {
+pub(crate) fn validate_password(p: &str) -> AppResult<()> {
     if p.len() < 8 {
         return Err(AppError::InvalidInput(
             "password must be at least 8 characters".into(),

backend/src/api/bookmarks.rs

@@ -67,14 +67,7 @@ async fn create(
     // the foreign-key violation collapse into a generic 500.
     repo::manga::get(&state.db, input.manga_id).await?;
     if let Some(chapter_id) = input.chapter_id {
-        let exists: Option<(Uuid,)> = sqlx::query_as(
-            "SELECT id FROM chapters WHERE id = $1 AND manga_id = $2",
-        )
-        .bind(chapter_id)
-        .bind(input.manga_id)
-        .fetch_optional(&state.db)
-        .await?;
-        if exists.is_none() {
+        if !repo::chapter::belongs_to_manga(&state.db, chapter_id, input.manga_id).await? {
             return Err(AppError::NotFound);
         }
     }

backend/src/api/mangas.rs

@@ -196,16 +196,14 @@ async fn create(
 
 async fn update(
     State(state): State<AppState>,
-    CurrentUser(_user): CurrentUser,
+    CurrentUser(user): CurrentUser,
     Path(id): Path<Uuid>,
     Json(patch): Json<MangaPatch>,
 ) -> AppResult<Json<MangaDetail>> {
-    // TODO(auth): until uploaders are tracked (Phase 5), any signed-in
-    // user can edit any manga. Restrict to uploader + admin once that
-    // column lands.
     if !repo::manga::exists(&state.db, id).await? {
         return Err(AppError::NotFound);
     }
+    require_can_edit(&state, id, user.id).await?;
 
     if let Some(ref status) = patch.status {
         let trimmed = status.trim();
@@ -269,16 +267,14 @@ async fn update(
 /// `MangaDetail`.
 async fn put_cover(
     State(state): State<AppState>,
-    CurrentUser(_user): CurrentUser,
+    CurrentUser(user): CurrentUser,
     Path(id): Path<Uuid>,
     mut multipart: Multipart,
 ) -> AppResult<Json<MangaDetail>> {
-    // TODO(auth): until uploaders are tracked (Phase 5), any signed-in
-    // user can edit any manga's cover. Restrict to uploader + admin
-    // once that column lands.
     if !repo::manga::exists(&state.db, id).await? {
         return Err(AppError::NotFound);
     }
+    require_can_edit(&state, id, user.id).await?;
 
     let mut cover: Option<UploadedImage> = None;
     while let Some(field) = next_field(&mut multipart).await? {
@@ -320,13 +316,13 @@ async fn put_cover(
 /// with the unchanged detail.
 async fn delete_cover(
     State(state): State<AppState>,
-    CurrentUser(_user): CurrentUser,
+    CurrentUser(user): CurrentUser,
     Path(id): Path<Uuid>,
 ) -> AppResult<Json<MangaDetail>> {
-    // TODO(auth): same caveat as put_cover.
     if !repo::manga::exists(&state.db, id).await? {
         return Err(AppError::NotFound);
     }
+    require_can_edit(&state, id, user.id).await?;
     if let Some(key) = repo::manga::get(&state.db, id).await?.cover_image_path {
         match state.storage.delete(&key).await {
             Ok(()) | Err(StorageError::NotFound) => {}
@@ -348,6 +344,7 @@ async fn attach_tag(
     Path(id): Path<Uuid>,
     Json(body): Json<AttachTagBody>,
 ) -> AppResult<(StatusCode, Json<TagRef>)> {
+    validate_tag_name(&body.name)?;
     if !repo::manga::exists(&state.db, id).await? {
         return Err(AppError::NotFound);
     }
@@ -394,6 +391,27 @@ async fn detach_tag(
     }
 }
 
+/// Request-side validation for `POST /mangas/:id/tags` body. Mirrors
+/// the repo-level cap in `repo::tag::upsert_by_name` (max 64 chars
+/// after trim) but surfaces the failure at the handler boundary with
+/// the same envelope shape other validations use.
+fn validate_tag_name(name: &str) -> AppResult<()> {
+    let trimmed = name.trim();
+    if trimmed.is_empty() {
+        return Err(AppError::ValidationFailed {
+            message: "tag name cannot be empty".into(),
+            details: json!({ "name": "required" }),
+        });
+    }
+    if trimmed.chars().count() > 64 {
+        return Err(AppError::ValidationFailed {
+            message: "tag name too long".into(),
+            details: json!({ "name": "max 64 characters" }),
+        });
+    }
+    Ok(())
+}
+
 fn validate_new_manga(input: &NewManga) -> AppResult<()> {
     if input.title.trim().is_empty() {
         return Err(AppError::ValidationFailed {
@@ -413,6 +431,30 @@ fn validate_new_manga(input: &NewManga) -> AppResult<()> {
     Ok(())
 }
 
+/// Authorisation gate for manga mutations. The manga is assumed to
+/// exist (the caller runs [`repo::manga::exists`] first so a missing id
+/// surfaces as `NotFound`, not `Forbidden`).
+///
+/// Rule: a non-NULL `uploaded_by` must match the current user. Legacy
+/// rows with `uploaded_by IS NULL` (pre-migration-0011) are still
+/// editable by any signed-in user — there's nobody to gate on yet, and
+/// the historical-data note in 0011 acknowledges the gap. Once an
+/// admin role lands the NULL case can flip to admin-only.
+///
+/// Returns `Forbidden` (not `NotFound`) on owner mismatch — mangas
+/// are listable via `GET /mangas`, so existence isn't a secret and
+/// the more accurate 403 is fine. This deliberately differs from
+/// `repo::collection::require_owner`, which collapses both states to
+/// `NotFound` because collections are private to a user and existence
+/// itself is information worth hiding from non-owners.
+async fn require_can_edit(state: &AppState, manga_id: Uuid, user_id: Uuid) -> AppResult<()> {
+    match repo::manga::uploaded_by(&state.db, manga_id).await? {
+        Some(owner) if owner != user_id => Err(AppError::Forbidden),
+        // Some(owner) == user_id (good) or None (legacy row, no owner).
+        _ => Ok(()),
+    }
+}
+
 async fn validate_genre_ids(state: &AppState, ids: &[Uuid]) -> AppResult<()> {
     if ids.is_empty() {
         return Ok(());

backend/src/api/mod.rs

@@ -1,3 +1,4 @@
+pub mod admin;
 pub mod auth;
 pub mod authors;
 pub mod bookmarks;
@@ -28,4 +29,5 @@ pub fn routes() -> Router<AppState> {
         .merge(authors::routes())
         .merge(collections::routes())
         .merge(history::routes())
+        .merge(admin::routes())
 }

backend/src/app.rs

@@ -3,8 +3,10 @@ use std::sync::atomic::AtomicBool;
 
 use anyhow::Context;
 use async_trait::async_trait;
-use axum::extract::DefaultBodyLimit;
+use axum::extract::{DefaultBodyLimit, FromRequestParts, Request, State};
 use axum::http::{HeaderName, HeaderValue, Method};
+use axum::middleware::{self, Next};
+use axum::response::Response;
 use axum::Router;
 use sqlx::postgres::PgPoolOptions;
 use sqlx::PgPool;
@@ -12,15 +14,19 @@ use tokio_util::sync::CancellationToken;
 use tower_http::cors::{AllowOrigin, CorsLayer};
 use tower_http::trace::TraceLayer;
 
-use crate::config::{AuthConfig, Config, CrawlerConfig, CrawlerModePref, UploadConfig};
+use crate::auth::extractor::CurrentUser;
+use crate::auth::rate_limit::AuthRateLimiter;
+use crate::error::AppError;
+use crate::config::{AuthConfig, Config, CrawlerConfig, UploadConfig};
 use crate::crawler::browser_manager::{self, BrowserManager};
 use crate::crawler::content::{self, SyncOutcome};
 use crate::crawler::daemon::{self, ChapterDispatcher, DaemonConfig, MetadataPass};
 use crate::crawler::jobs::JobPayload;
 use crate::crawler::pipeline::{self, MetadataStats};
 use crate::crawler::rate_limit::HostRateLimiters;
+use crate::crawler::resync::{RealResyncService, ResyncService};
+use crate::crawler::safety::DownloadAllowlist;
 use crate::crawler::session;
-use crate::crawler::source::{target as target_source, DiscoverMode};
 use crate::repo;
 use crate::storage::{LocalStorage, Storage};
 
@@ -30,6 +36,16 @@ pub struct AppState {
     pub storage: Arc<dyn Storage>,
     pub auth: AuthConfig,
     pub upload: UploadConfig,
+    /// Shared rate limiter guarding the `/auth/*` mutation endpoints.
+    /// One instance per AppState so tests stay isolated across the
+    /// same process.
+    pub auth_limiter: Arc<AuthRateLimiter>,
+    /// Admin-triggered force resync. `None` when the crawler daemon
+    /// is disabled (`CRAWLER_DAEMON=false`); admin handlers gate on
+    /// `.is_some()` and return 503 otherwise. Set by [`build`] from the
+    /// same wiring that builds the daemon's chapter dispatcher, so a
+    /// force resync uses the daemon's BrowserManager + rate limiters.
+    pub resync: Option<Arc<dyn ResyncService>>,
 }
 
 /// Bundle returned by [`build`]. The router is what `axum::serve` consumes;
@@ -55,30 +71,50 @@ pub async fn build(config: Config) -> anyhow::Result<AppHandle> {
         .await?;
     sqlx::migrate!("./migrations").run(&db).await?;
 
+    if let Some((username, password)) = config.admin_bootstrap.as_ref() {
+        repo::user::bootstrap_admin(&db, username, password)
+            .await
+            .context("bootstrap_admin from ADMIN_USERNAME/ADMIN_PASSWORD env")?;
+        tracing::info!(admin_username = %username, "admin bootstrap ensured");
+    }
+
     let storage: Arc<dyn Storage> = Arc::new(LocalStorage::new(config.storage_dir.clone()));
 
-    let daemon = if config.crawler.daemon_enabled {
-        Some(spawn_crawler_daemon(db.clone(), Arc::clone(&storage), &config.crawler).await?)
+    let (daemon, resync) = if config.crawler.daemon_enabled {
+        let spawned = spawn_crawler_daemon(db.clone(), Arc::clone(&storage), &config.crawler).await?;
+        (Some(spawned.handle), Some(spawned.resync))
     } else {
         tracing::info!("crawler daemon disabled (CRAWLER_DAEMON=false)");
-        None
+        (None, None)
     };
 
+    let auth_limiter = Arc::new(AuthRateLimiter::new(config.auth.rate_limit));
     let state = AppState {
         db,
         storage,
         auth: config.auth.clone(),
         upload: config.upload.clone(),
+        auth_limiter,
+        resync,
     };
     let router = router(state).layer(cors_layer(&config.cors_allowed_origins));
     Ok(AppHandle { router, daemon })
 }
 
+/// Bundle returned by [`spawn_crawler_daemon`]. The handle owns the
+/// daemon's tasks; `resync` is the operator-trigger service shared with
+/// `AppState` so admin endpoints can call into the same browser /
+/// rate-limit machinery.
+struct SpawnedDaemon {
+    handle: daemon::DaemonHandle,
+    resync: Arc<dyn ResyncService>,
+}
+
 async fn spawn_crawler_daemon(
     db: PgPool,
     storage: Arc<dyn Storage>,
     cfg: &CrawlerConfig,
-) -> anyhow::Result<daemon::DaemonHandle> {
+) -> anyhow::Result<SpawnedDaemon> {
     // Reqwest client with cookie jar pre-seeded so CDN image fetches
     // include PHPSESSID. Same shape as bin/crawler.rs main().
     let cookie_jar = Arc::new(reqwest::cookie::Jar::default());
@@ -109,29 +145,49 @@ async fn spawn_crawler_daemon(
     }
     let rate = Arc::new(rate);
 
+    let tor = crate::crawler::tor::TorController::from_parts(
+        cfg.tor_control_url.as_deref(),
+        cfg.tor_control_password.as_deref(),
+        cfg.tor_control_cookie_path.as_deref(),
+    )
+    .context("build TorController from CRAWLER_TOR_CONTROL_* env")?
+    .map(Arc::new);
+    if let Some(t) = &tor {
+        tracing::info!(?t, "TOR control configured; transient pages will trigger NEWNYM");
+    }
+    let tor_recircuit_max = cfg.tor_recircuit_max_attempts;
+
     // Browser manager. on_launch re-injects PHPSESSID on every fresh
     // chromium spawn so an idle teardown followed by re-launch stays
     // authenticated without operator action.
     let mut launch_opts = cfg.browser.clone();
     if let Some(proxy) = &cfg.proxy {
-        launch_opts.extra_args.push(format!("--proxy-server={proxy}"));
+        let chromium_proxy = crate::crawler::url_utils::chromium_proxy_arg(proxy);
+        launch_opts.extra_args.push(format!("--proxy-server={chromium_proxy}"));
     }
     let on_launch = match (&cfg.phpsessid, &cfg.cookie_domain, &cfg.start_url) {
         (Some(sid), Some(domain), Some(start_url)) => {
             let sid = sid.clone();
             let domain = domain.clone();
             let start_url = start_url.clone();
+            let tor_for_launch = tor.as_ref().map(Arc::clone);
             let on_launch: browser_manager::OnLaunch = Arc::new(move |browser| {
                 let sid = sid.clone();
                 let domain = domain.clone();
                 let start_url = start_url.clone();
+                let tor_for_launch = tor_for_launch.as_ref().map(Arc::clone);
                 Box::pin(async move {
                     session::inject_phpsessid(&browser, &sid, &domain)
                         .await
                         .context("on_launch: inject_phpsessid")?;
-                    session::verify_session(&browser, &start_url)
-                        .await
-                        .context("on_launch: verify_session")?;
+                    session::verify_session_with_recircuit(
+                        &browser,
+                        &start_url,
+                        tor_for_launch.as_deref(),
+                        tor_recircuit_max,
+                    )
+                    .await
+                    .context("on_launch: verify_session")?;
                     Ok(())
                 })
             });
@@ -151,18 +207,34 @@ async fn spawn_crawler_daemon(
             http: http.clone(),
             rate: Arc::clone(&rate),
             start_url: url.clone(),
-            mode_pref: cfg.mode,
-            incremental_stop_after: cfg.incremental_stop_after,
+            manga_limit: cfg.manga_limit,
+            download_allowlist: cfg.download_allowlist.clone(),
+            max_image_bytes: cfg.max_image_bytes,
+            tor: tor.as_ref().map(Arc::clone),
         });
         m
     });
 
     let dispatcher: Arc<dyn ChapterDispatcher> = Arc::new(RealChapterDispatcher {
+        browser_manager: Arc::clone(&browser_manager),
+        db: db.clone(),
+        storage: Arc::clone(&storage),
+        http: http.clone(),
+        rate: Arc::clone(&rate),
+        download_allowlist: cfg.download_allowlist.clone(),
+        max_image_bytes: cfg.max_image_bytes,
+        tor: tor.as_ref().map(Arc::clone),
+    });
+
+    let resync: Arc<dyn ResyncService> = Arc::new(RealResyncService {
         browser_manager: Arc::clone(&browser_manager),
         db: db.clone(),
         storage: Arc::clone(&storage),
         http,
         rate: Arc::clone(&rate),
+        download_allowlist: cfg.download_allowlist.clone(),
+        max_image_bytes: cfg.max_image_bytes,
+        tor: tor.as_ref().map(Arc::clone),
     });
 
     // Shared cancellation: daemon shutdown cancels the BrowserManager's
@@ -199,7 +271,10 @@ async fn spawn_crawler_daemon(
         },
     );
 
-    Ok(daemon_handle)
+    Ok(SpawnedDaemon {
+        handle: daemon_handle,
+        resync,
+    })
 }
 
 // Real impls of the daemon traits, owning the browser manager + I/O. Kept
@@ -214,76 +289,65 @@ struct RealMetadataPass {
     http: reqwest::Client,
     rate: Arc<HostRateLimiters>,
     start_url: String,
-    mode_pref: CrawlerModePref,
-    incremental_stop_after: usize,
+    manga_limit: usize,
+    download_allowlist: DownloadAllowlist,
+    max_image_bytes: usize,
+    tor: Option<Arc<crate::crawler::tor::TorController>>,
 }
 
 #[async_trait]
 impl MetadataPass for RealMetadataPass {
     async fn run(&self) -> anyhow::Result<MetadataStats> {
-        let mode = resolve_mode(
-            &self.db,
-            target_source::SOURCE_ID,
-            self.mode_pref,
-            self.incremental_stop_after,
-        )
-        .await?;
-        pipeline::run_metadata_pass(
+        let result = pipeline::run_metadata_pass(
             &self.browser_manager,
             &self.db,
             self.storage.as_ref(),
             &self.http,
             &self.rate,
             &self.start_url,
-            0,
+            self.manga_limit,
             false,
-            mode,
+            &self.download_allowlist,
+            self.max_image_bytes,
+            self.tor.as_deref(),
+        )
+        .await;
+        if let Err(e) = &result {
+            if crate::crawler::nav::anyhow_looks_browser_dead(e) {
+                self.browser_manager.invalidate().await;
+            }
+        }
+        // Cover backfill follows the metadata pass even when the pass
+        // errored — the early-stop walk can complete its work and bail
+        // late, and a transient browser failure shouldn't cancel the
+        // residual cover backlog. The backfill has its own per-call cap
+        // so a runaway error stream can't monopolise the tick.
+        match pipeline::backfill_missing_covers(
+            &self.browser_manager,
+            &self.db,
+            self.storage.as_ref(),
+            &self.http,
+            &self.rate,
+            pipeline::COVER_BACKFILL_DEFAULT_MAX,
+            &self.download_allowlist,
+            self.max_image_bytes,
+            self.tor.as_deref(),
         )
         .await
-    }
-}
-
-/// Pick the active mode for this tick. `Explicit` short-circuits the
-/// DB lookup. `Auto` reads `seed_completed_at`: missing → Backfill
-/// (initial seed for this source), present → Incremental with the
-/// configured threshold.
-///
-/// A DB error during the Auto lookup propagates as `Err` rather than
-/// silently degrading to Backfill — the daemon's `run_tick` catches
-/// the error, logs, and skips the tick. That's safer than running a
-/// full re-backfill (including a drop pass against stale-looking rows)
-/// when the DB is flaky.
-async fn resolve_mode(
-    db: &PgPool,
-    source_id: &str,
-    pref: CrawlerModePref,
-    incremental_stop_after: usize,
-) -> anyhow::Result<DiscoverMode> {
-    match pref {
-        CrawlerModePref::Explicit(m) => {
-            tracing::info!(?m, "crawler mode: explicit (CRAWLER_MODE override)");
-            Ok(m)
-        }
-        CrawlerModePref::Auto => {
-            let seeded = repo::crawler::seed_completed_at(db, source_id)
-                .await
-                .context("seed_completed_at lookup for mode auto-detection")?;
-            match seeded {
-                Some(at) => {
-                    tracing::info!(
-                        seed_completed_at = %at.to_rfc3339(),
-                        "crawler mode: auto → incremental (seed previously completed)"
-                    );
-                    Ok(DiscoverMode::Incremental {
-                        stop_after_unchanged: incremental_stop_after,
-                    })
+        {
+            Ok(stats) => {
+                if stats.considered > 0 {
+                    tracing::info!(?stats, "cover backfill complete");
                 }
-                None => {
-                    tracing::info!("crawler mode: auto → backfill (no seed marker for source)");
-                    Ok(DiscoverMode::Backfill)
+            }
+            Err(e) => {
+                tracing::warn!(error = ?e, "cover backfill failed");
+                if crate::crawler::nav::anyhow_looks_browser_dead(&e) {
+                    self.browser_manager.invalidate().await;
                 }
             }
         }
+        result
     }
 }
 
@@ -293,6 +357,9 @@ struct RealChapterDispatcher {
     storage: Arc<dyn Storage>,
     http: reqwest::Client,
     rate: Arc<HostRateLimiters>,
+    download_allowlist: DownloadAllowlist,
+    max_image_bytes: usize,
+    tor: Option<Arc<crate::crawler::tor::TorController>>,
 }
 
 #[async_trait]
@@ -304,24 +371,15 @@ impl ChapterDispatcher for RealChapterDispatcher {
                 chapter_id,
                 source_chapter_key: _,
             } => {
-                // Look up manga_id + source_url for this chapter.
-                let row: Option<(uuid::Uuid, String)> = sqlx::query_as(
-                    "SELECT c.manga_id, cs.source_url \
-                       FROM chapters c \
-                       JOIN chapter_sources cs ON cs.chapter_id = c.id \
-                      WHERE c.id = $1 \
-                      LIMIT 1",
-                )
-                .bind(chapter_id)
-                .fetch_optional(&self.db)
-                .await
-                .context("look up chapter for dispatch")?;
+                let row = repo::chapter::dispatch_target(&self.db, chapter_id)
+                    .await
+                    .context("look up chapter for dispatch")?;
                 let Some((manga_id, source_url)) = row else {
                     // Chapter (or its source row) is gone — ack done.
                     return Ok(SyncOutcome::Skipped);
                 };
                 let lease = self.browser_manager.acquire().await?;
-                let outcome = content::sync_chapter_content(
+                let result = content::sync_chapter_content(
                     &lease,
                     &self.db,
                     self.storage.as_ref(),
@@ -331,14 +389,25 @@ impl ChapterDispatcher for RealChapterDispatcher {
                     manga_id,
                     &source_url,
                     false,
+                    &self.download_allowlist,
+                    self.max_image_bytes,
+                    self.tor.as_deref(),
                 )
-                .await?;
+                .await;
                 drop(lease);
-                Ok(outcome)
+                match result {
+                    Ok(outcome) => Ok(outcome),
+                    Err(e) => {
+                        if crate::crawler::nav::anyhow_looks_browser_dead(&e) {
+                            self.browser_manager.invalidate().await;
+                        }
+                        Err(e)
+                    }
+                }
             }
             // Other payload kinds aren't dispatched by this daemon yet —
-            // metadata-driven jobs (Discover/SyncManga/SyncChapterList)
-            // are handled inline by the cron's metadata pass.
+            // SyncManga / SyncChapterList are handled inline by the cron's
+            // metadata pass.
             _ => Ok(SyncOutcome::Skipped),
         }
     }
@@ -350,11 +419,62 @@ pub fn router(state: AppState) -> Router {
     let max_request_bytes = state.upload.max_request_bytes;
     Router::new()
         .nest("/api/v1", crate::api::routes())
+        .layer(middleware::from_fn_with_state(
+            state.clone(),
+            private_mode_guard,
+        ))
         .layer(DefaultBodyLimit::max(max_request_bytes))
         .with_state(state)
         .layer(TraceLayer::new_for_http())
 }
 
+/// Paths reachable anonymously even when `PRIVATE_MODE=true`. Login and
+/// logout are needed for the auth flow itself; `/health` is reserved
+/// for load-balancer probes; `/auth/config` lets the frontend decide
+/// whether to render the login form or its anonymous alternatives;
+/// `/auth/register` is exempted from the gate so the handler can
+/// return its informative `registration_disabled` 403 (the same code
+/// public-mode deployments use when `ALLOW_SELF_REGISTER=false`) —
+/// the handler itself force-blocks the request body in private mode,
+/// so no account ever gets created here. Everything else demands a
+/// valid session cookie or bearer token.
+fn is_public_in_private_mode(path: &str) -> bool {
+    matches!(
+        path,
+        "/api/v1/health"
+            | "/api/v1/auth/config"
+            | "/api/v1/auth/login"
+            | "/api/v1/auth/logout"
+            | "/api/v1/auth/register"
+    )
+}
+
+/// Site-wide auth gate for `PRIVATE_MODE=true`. With the flag off this
+/// is a no-op pass-through, so public deployments take no extra DB
+/// hit. With it on, the guard reuses [`CurrentUser`] — the same
+/// session-cookie-then-bearer-token logic the per-handler extractor
+/// uses — so the two paths can never drift.
+async fn private_mode_guard(
+    State(state): State<AppState>,
+    req: Request,
+    next: Next,
+) -> Result<Response, AppError> {
+    if !state.auth.private_mode {
+        return Ok(next.run(req).await);
+    }
+    if is_public_in_private_mode(req.uri().path()) {
+        return Ok(next.run(req).await);
+    }
+    let (mut parts, body) = req.into_parts();
+    match CurrentUser::from_request_parts(&mut parts, &state).await {
+        Ok(_) => {
+            let req = Request::from_parts(parts, body);
+            Ok(next.run(req).await)
+        }
+        Err(_) => Err(AppError::Unauthenticated),
+    }
+}
+
 pub(crate) fn cors_layer(allowed_origins: &[String]) -> CorsLayer {
     if allowed_origins.is_empty() {
         // Same-origin only — no CORS headers emitted.

backend/src/auth/extractor.rs

@@ -1,11 +1,19 @@
-//! `CurrentUser` axum extractor.
+//! Auth extractors.
 //!
-//! Resolves a request to a logged-in user by trying, in order:
-//! 1. a `mangalord_session` cookie (session lookup by `sha256(value)`);
-//! 2. an `Authorization: Bearer <token>` header (api_token lookup).
+//! Three extractors are available, in increasing strictness:
 //!
-//! Both paths look up by hash, never by raw value. Failure to resolve
-//! either way returns 401 via `AppError::Unauthenticated`.
+//! - [`CurrentUser`] — accepts either a session cookie or an
+//!   `Authorization: Bearer <token>` header. Used by ordinary
+//!   authenticated endpoints where bot tokens are first-class clients.
+//! - [`CurrentSessionUser`] — accepts only the session cookie. Used as
+//!   the substrate for admin extraction so bot tokens cannot authenticate
+//!   as the admin (see [`RequireAdmin`]).
+//! - [`RequireAdmin`] — composes over [`CurrentSessionUser`] and
+//!   additionally requires `user.is_admin`. Returns 403 for
+//!   authenticated-but-not-admin, 401 otherwise.
+//!
+//! All lookups go by `sha256(raw_token)` — the raw value is never stored
+//! in the database.
 
 use axum::async_trait;
 use axum::extract::FromRequestParts;
@@ -61,3 +69,54 @@ impl FromRequestParts<AppState> for CurrentUser {
         Err(AppError::Unauthenticated)
     }
 }
+
+/// Cookie-only authentication. Bot/API tokens are explicitly NOT accepted
+/// here — this is the substrate for [`RequireAdmin`] and exists precisely
+/// to keep admin authority out of bearer-token reach.
+pub struct CurrentSessionUser(pub User);
+
+#[async_trait]
+impl FromRequestParts<AppState> for CurrentSessionUser {
+    type Rejection = AppError;
+
+    async fn from_request_parts(
+        parts: &mut Parts,
+        state: &AppState,
+    ) -> Result<Self, Self::Rejection> {
+        let jar = CookieJar::from_headers(&parts.headers);
+        let cookie = jar
+            .get(SESSION_COOKIE_NAME)
+            .ok_or(AppError::Unauthenticated)?;
+        let hash = hash_token(cookie.value());
+        let session = repo::session::find_active(&state.db, &hash)
+            .await?
+            .ok_or(AppError::Unauthenticated)?;
+        let user = repo::user::find_by_id(&state.db, session.user_id)
+            .await?
+            .ok_or(AppError::Unauthenticated)?;
+        Ok(CurrentSessionUser(user))
+    }
+}
+
+/// Admin-only. Composes over [`CurrentSessionUser`] so bot tokens are
+/// rejected at the auth step (401) rather than the role step (403).
+/// The user row is re-read every request, so demotion takes effect on
+/// the very next call without needing to purge sessions.
+pub struct RequireAdmin(pub User);
+
+#[async_trait]
+impl FromRequestParts<AppState> for RequireAdmin {
+    type Rejection = AppError;
+
+    async fn from_request_parts(
+        parts: &mut Parts,
+        state: &AppState,
+    ) -> Result<Self, Self::Rejection> {
+        let CurrentSessionUser(user) =
+            CurrentSessionUser::from_request_parts(parts, state).await?;
+        if !user.is_admin {
+            return Err(AppError::Forbidden);
+        }
+        Ok(RequireAdmin(user))
+    }
+}

backend/src/auth/mod.rs

@@ -7,4 +7,5 @@
 
 pub mod extractor;
 pub mod password;
+pub mod rate_limit;
 pub mod token;

backend/src/auth/rate_limit.rs

@@ -0,0 +1,179 @@
+//! Per-process token-bucket rate limiter for the auth endpoints.
+//!
+//! Protects `/auth/login`, `/auth/register`, and `/auth/me/password`
+//! from credential stuffing / password spraying / username probing.
+//!
+//! The current deploy puts SvelteKit's hooks.server.ts proxy in front
+//! of axum without forwarding the original client IP (no
+//! `X-Forwarded-For`), so per-IP buckets would all collapse to the
+//! proxy container's address. Until the proxy learns to forward the
+//! peer address, a single global bucket gives equivalent protection
+//! against mass-attack patterns and trades a small DoS surface
+//! (legitimate users sharing the limit) for simplicity.
+//!
+//! Each `AppState` carries its own [`AuthRateLimiter`] instance, so
+//! tests run in isolated buckets and won't bleed across `#[sqlx::test]`
+//! cases that share a process.
+
+use std::sync::Mutex;
+use std::time::Instant;
+
+/// Tunable limits. `per_sec == 0` disables the limiter — used by the
+/// test harness and by anyone who wants to opt out via env config.
+#[derive(Clone, Copy, Debug)]
+pub struct RateLimitConfig {
+    pub per_sec: u32,
+    pub burst: u32,
+}
+
+impl Default for RateLimitConfig {
+    /// Disabled by default. The production `AuthConfig::from_env`
+    /// overrides to a real limit; the test harness keeps the default
+    /// so existing tests don't flake against shared buckets.
+    fn default() -> Self {
+        Self {
+            per_sec: 0,
+            burst: 0,
+        }
+    }
+}
+
+/// Production defaults: 5 requests/sec sustained, 10-request burst.
+/// Tight enough to make brute force impractical, loose enough that a
+/// real user mistyping their password three times in a row doesn't
+/// hit it.
+pub const PRODUCTION_PER_SEC: u32 = 5;
+pub const PRODUCTION_BURST: u32 = 10;
+
+struct Bucket {
+    tokens: f64,
+    last_refill: Instant,
+}
+
+/// Outcome of [`AuthRateLimiter::try_acquire`]. When `Denied`, the
+/// caller can use `retry_after_secs` for a `Retry-After: N` header
+/// (RFC 6585 §4) so well-behaved clients back off correctly rather
+/// than retrying in a tight loop.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum AcquireResult {
+    Allowed,
+    Denied { retry_after_secs: u64 },
+}
+
+/// Single-bucket token-bucket limiter. `try_acquire` is cheap (one
+/// mutex acquire, no allocations) so the auth path doesn't pay a real
+/// cost for the check.
+pub struct AuthRateLimiter {
+    cfg: RateLimitConfig,
+    bucket: Mutex<Bucket>,
+}
+
+impl AuthRateLimiter {
+    pub fn new(cfg: RateLimitConfig) -> Self {
+        Self {
+            cfg,
+            bucket: Mutex::new(Bucket {
+                tokens: cfg.burst as f64,
+                last_refill: Instant::now(),
+            }),
+        }
+    }
+
+    /// Consume one token if available. Returns `Denied` with a
+    /// rounded-up seconds-until-refill so the caller can emit a
+    /// `Retry-After` header.
+    pub fn try_acquire(&self) -> AcquireResult {
+        if self.cfg.per_sec == 0 {
+            return AcquireResult::Allowed;
+        }
+        let now = Instant::now();
+        let mut bucket = self.bucket.lock().expect("rate limiter mutex poisoned");
+        let elapsed = now.duration_since(bucket.last_refill).as_secs_f64();
+        bucket.tokens =
+            (bucket.tokens + elapsed * f64::from(self.cfg.per_sec)).min(f64::from(self.cfg.burst));
+        bucket.last_refill = now;
+        if bucket.tokens >= 1.0 {
+            bucket.tokens -= 1.0;
+            AcquireResult::Allowed
+        } else {
+            // ceil((1 - tokens) / per_sec), minimum 1 — a `Retry-After: 0`
+            // would tell clients to retry immediately, which is what we're
+            // actively trying to discourage.
+            let deficit = 1.0 - bucket.tokens;
+            let wait_secs = (deficit / f64::from(self.cfg.per_sec)).ceil() as u64;
+            AcquireResult::Denied {
+                retry_after_secs: wait_secs.max(1),
+            }
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn disabled_limiter_always_allows() {
+        let rl = AuthRateLimiter::new(RateLimitConfig {
+            per_sec: 0,
+            burst: 0,
+        });
+        for _ in 0..1000 {
+            assert_eq!(rl.try_acquire(), AcquireResult::Allowed);
+        }
+    }
+
+    #[test]
+    fn burst_lets_through_initial_window_then_blocks() {
+        // 0 refill, burst 3 → first three pass, fourth blocks.
+        let rl = AuthRateLimiter::new(RateLimitConfig {
+            per_sec: 1,
+            burst: 3,
+        });
+        assert_eq!(rl.try_acquire(), AcquireResult::Allowed);
+        assert_eq!(rl.try_acquire(), AcquireResult::Allowed);
+        assert_eq!(rl.try_acquire(), AcquireResult::Allowed);
+        match rl.try_acquire() {
+            AcquireResult::Denied { retry_after_secs } => {
+                // Bucket is at ~0 tokens, refill rate 1/sec → ~1s wait.
+                assert!(
+                    retry_after_secs >= 1,
+                    "retry_after must be at least 1s, got {retry_after_secs}"
+                );
+            }
+            AcquireResult::Allowed => panic!("fourth request must be denied"),
+        }
+    }
+
+    #[test]
+    fn tokens_refill_over_time() {
+        // 10/sec → after ~120ms we should have at least one token back.
+        let rl = AuthRateLimiter::new(RateLimitConfig {
+            per_sec: 10,
+            burst: 1,
+        });
+        assert_eq!(rl.try_acquire(), AcquireResult::Allowed);
+        assert!(matches!(rl.try_acquire(), AcquireResult::Denied { .. }));
+        std::thread::sleep(std::time::Duration::from_millis(150));
+        assert_eq!(
+            rl.try_acquire(),
+            AcquireResult::Allowed,
+            "token should have refilled"
+        );
+    }
+
+    #[test]
+    fn retry_after_scales_inversely_with_refill_rate() {
+        // 1/sec → wait ~1s after burst exhausted.
+        // 10/sec → wait <1s, but we clamp to a minimum of 1s.
+        let slow = AuthRateLimiter::new(RateLimitConfig {
+            per_sec: 1,
+            burst: 1,
+        });
+        slow.try_acquire();
+        match slow.try_acquire() {
+            AcquireResult::Denied { retry_after_secs } => assert_eq!(retry_after_secs, 1),
+            _ => panic!("expected Denied"),
+        }
+    }
+}

backend/src/bin/crawler.rs

@@ -31,7 +31,6 @@ use mangalord::crawler::content::{self, SyncOutcome};
 use mangalord::crawler::pipeline;
 use mangalord::crawler::rate_limit::HostRateLimiters;
 use mangalord::crawler::session;
-use mangalord::crawler::source::DiscoverMode;
 use mangalord::storage::{LocalStorage, Storage};
 use sqlx::postgres::PgPoolOptions;
 use sqlx::PgPool;
@@ -63,8 +62,6 @@ async fn main() -> anyhow::Result<()> {
     let cdn_rate_ms = env_u64("CRAWLER_CDN_RATE_MS", rate_ms);
     let limit = env_u64("CRAWLER_LIMIT", 0) as usize;
     let skip_chapters = env_bool("CRAWLER_SKIP_CHAPTERS", false);
-    let incremental_stop_after = env_u64("CRAWLER_INCREMENTAL_STOP_AFTER", 20).max(1) as usize;
-    let mode = parse_crawler_mode(incremental_stop_after)?;
     let skip_chapter_content = env_bool("CRAWLER_SKIP_CHAPTER_CONTENT", false);
     let chapter_workers = env_u64("CRAWLER_CHAPTER_WORKERS", 1).max(1) as usize;
     let force_refetch_chapters = env_bool("CRAWLER_FORCE_REFETCH_CHAPTERS", false);
@@ -81,6 +78,21 @@ async fn main() -> anyhow::Result<()> {
     let proxy_url = std::env::var("CRAWLER_PROXY")
         .ok()
         .filter(|s| !s.trim().is_empty());
+    let tor_control_url = std::env::var("CRAWLER_TOR_CONTROL_URL")
+        .ok()
+        .filter(|s| !s.trim().is_empty());
+    let tor_control_password = std::env::var("CRAWLER_TOR_CONTROL_PASSWORD")
+        .ok()
+        .filter(|s| !s.trim().is_empty());
+    let tor_control_cookie_path = std::env::var("CRAWLER_TOR_CONTROL_COOKIE_PATH")
+        .ok()
+        .filter(|s| !s.trim().is_empty())
+        .map(std::path::PathBuf::from);
+    let tor_recircuit_max_attempts: u32 = std::env::var("CRAWLER_TOR_RECIRCUIT_MAX_ATTEMPTS")
+        .ok()
+        .and_then(|s| s.parse().ok())
+        .unwrap_or(3)
+        .max(1);
     let keep_browser_open = env_bool("CRAWLER_KEEP_BROWSER_OPEN", false);
 
     let db = PgPoolOptions::new()
@@ -115,7 +127,8 @@ async fn main() -> anyhow::Result<()> {
 
     let mut options = LaunchOptions::from_env();
     if let Some(proxy) = &proxy_url {
-        options.extra_args.push(format!("--proxy-server={proxy}"));
+        let chromium_proxy = mangalord::crawler::url_utils::chromium_proxy_arg(proxy);
+        options.extra_args.push(format!("--proxy-server={chromium_proxy}"));
     }
     let keep_open = match (keep_browser_open, options.mode) {
         (true, BrowserMode::Headed) => true,
@@ -143,11 +156,21 @@ async fn main() -> anyhow::Result<()> {
         user_agent = ?user_agent,
         proxy = ?proxy_url,
         keep_open,
-        ?mode,
         storage_dir = %storage_dir.display(),
         "starting crawler"
     );
 
+    let tor = mangalord::crawler::tor::TorController::from_parts(
+        tor_control_url.as_deref(),
+        tor_control_password.as_deref(),
+        tor_control_cookie_path.as_deref(),
+    )
+    .context("build TorController from CRAWLER_TOR_CONTROL_* env")?
+    .map(Arc::new);
+    if let Some(t) = &tor {
+        tracing::info!(?t, "TOR control configured");
+    }
+
     // BrowserManager with idle_timeout = ZERO so the CLI keeps Chromium
     // alive for the entire run — same lifecycle as the old direct
     // `browser::launch()` flow. on_launch re-injects PHPSESSID + runs the
@@ -157,17 +180,24 @@ async fn main() -> anyhow::Result<()> {
             let sid = sid.clone();
             let domain = domain.clone();
             let start_url_clone = start_url.clone();
+            let tor_for_launch = tor.as_ref().map(Arc::clone);
             Arc::new(move |browser| {
                 let sid = sid.clone();
                 let domain = domain.clone();
                 let start_url = start_url_clone.clone();
+                let tor_for_launch = tor_for_launch.as_ref().map(Arc::clone);
                 Box::pin(async move {
                     session::inject_phpsessid(&browser, &sid, &domain)
                         .await
                         .context("inject_phpsessid")?;
-                    session::verify_session(&browser, &start_url)
-                        .await
-                        .context("verify_session")?;
+                    session::verify_session_with_recircuit(
+                        &browser,
+                        &start_url,
+                        tor_for_launch.as_deref(),
+                        tor_recircuit_max_attempts,
+                    )
+                    .await
+                    .context("verify_session")?;
                     Ok(())
                 })
             })
@@ -191,7 +221,7 @@ async fn main() -> anyhow::Result<()> {
         skip_chapter_content || !session_ready,
         chapter_workers,
         force_refetch_chapters,
-        mode,
+        tor.clone(),
     )
     .await;
 
@@ -221,7 +251,7 @@ async fn run(
     skip_chapter_content: bool,
     chapter_workers: usize,
     force_refetch_chapters: bool,
-    mode: DiscoverMode,
+    tor: Option<Arc<mangalord::crawler::tor::TorController>>,
 ) -> anyhow::Result<()> {
     let mut rate = HostRateLimiters::new(Duration::from_millis(rate_ms));
     if let Some(host) = cdn_host {
@@ -229,6 +259,39 @@ async fn run(
     }
     let rate = Arc::new(rate);
 
+    // SSRF defence: only download from the catalog host + CDN host
+    // (plus optional CRAWLER_DOWNLOAD_ALLOWLIST extras), and cap
+    // single-image downloads at CRAWLER_MAX_IMAGE_BYTES bytes.
+    // CRAWLER_ALLOW_ANY_HOST=true short-circuits the host check for
+    // sharded-CDN sources; private-IP and scheme guards still apply.
+    let allowlist = if env_bool("CRAWLER_ALLOW_ANY_HOST", false) {
+        mangalord::crawler::safety::DownloadAllowlist::allow_any()
+    } else {
+        let mut allow = mangalord::crawler::safety::DownloadAllowlist::new();
+        if let Ok(parsed) = reqwest::Url::parse(start_url) {
+            if let Some(h) = parsed.host_str() {
+                allow = allow.allow(h);
+            }
+        }
+        if let Some(host) = cdn_host {
+            allow = allow.allow(host);
+        }
+        if let Ok(extras) = std::env::var("CRAWLER_DOWNLOAD_ALLOWLIST") {
+            for piece in extras.split(',') {
+                let trimmed = piece.trim();
+                if !trimmed.is_empty() {
+                    allow = allow.allow(trimmed);
+                }
+            }
+        }
+        allow
+    };
+    let max_image_bytes: usize = std::env::var("CRAWLER_MAX_IMAGE_BYTES")
+        .ok()
+        .and_then(|s| s.parse().ok())
+        .unwrap_or(mangalord::crawler::safety::DEFAULT_MAX_IMAGE_BYTES);
+    let allowlist = Arc::new(allowlist);
+
     let stats = pipeline::run_metadata_pass(
         manager.as_ref(),
         db,
@@ -238,7 +301,9 @@ async fn run(
         start_url,
         limit,
         skip_chapters,
-        mode,
+        allowlist.as_ref(),
+        max_image_bytes,
+        tor.as_deref(),
     )
     .await?;
     tracing::info!(?stats, "metadata pass complete");
@@ -253,6 +318,9 @@ async fn run(
             "target",
             chapter_workers,
             force_refetch_chapters,
+            Arc::clone(&allowlist),
+            max_image_bytes,
+            tor.clone(),
         )
         .await?;
     }
@@ -276,6 +344,9 @@ async fn sync_bookmarked_chapter_content(
     source_id: &str,
     workers: usize,
     force_refetch: bool,
+    allowlist: Arc<mangalord::crawler::safety::DownloadAllowlist>,
+    max_image_bytes: usize,
+    tor: Option<Arc<mangalord::crawler::tor::TorController>>,
 ) -> anyhow::Result<()> {
     let pending: Vec<(Uuid, Uuid, String)> = sqlx::query_as(
         r#"
@@ -312,6 +383,8 @@ async fn sync_bookmarked_chapter_content(
             let storage = Arc::clone(&storage);
             let rate = Arc::clone(&rate);
             let manager = Arc::clone(&manager);
+            let allowlist = Arc::clone(&allowlist);
+            let tor = tor.clone();
             let stats = &stats;
             async move {
                 if session_expired.load(std::sync::atomic::Ordering::Relaxed) {
@@ -336,6 +409,9 @@ async fn sync_bookmarked_chapter_content(
                     manga_id,
                     &source_url,
                     force_refetch,
+                    allowlist.as_ref(),
+                    max_image_bytes,
+                    tor.as_deref(),
                 )
                 .await;
                 drop(lease);
@@ -397,38 +473,6 @@ fn resolve_start_url() -> anyhow::Result<String> {
     })
 }
 
-/// Parse the CLI's `CRAWLER_MODE`. Defaults to `backfill` because the
-/// binary is operator-driven (manual reseeds, force-refetches) — the
-/// auto-detect logic lives in the daemon. `auto` is rejected because
-/// the CLI has no DB state to consult before the run.
-fn parse_crawler_mode(incremental_stop_after: usize) -> anyhow::Result<DiscoverMode> {
-    parse_crawler_mode_str(
-        std::env::var("CRAWLER_MODE").ok().as_deref(),
-        incremental_stop_after,
-    )
-}
-
-/// Pure variant of [`parse_crawler_mode`] — testable without env-var
-/// mutation.
-fn parse_crawler_mode_str(
-    raw: Option<&str>,
-    incremental_stop_after: usize,
-) -> anyhow::Result<DiscoverMode> {
-    match raw.map(|s| s.trim().to_ascii_lowercase()).as_deref() {
-        None | Some("") | Some("backfill") => Ok(DiscoverMode::Backfill),
-        Some("incremental") => Ok(DiscoverMode::Incremental {
-            stop_after_unchanged: incremental_stop_after,
-        }),
-        Some("auto") => Err(anyhow!(
-            "CRAWLER_MODE=auto isn't supported by the CLI (use backfill or incremental); \
-             the daemon does auto-detection"
-        )),
-        Some(other) => Err(anyhow!(
-            "CRAWLER_MODE must be one of: backfill, incremental (got {other:?})"
-        )),
-    }
-}
-
 fn env_u64(name: &str, default: u64) -> u64 {
     std::env::var(name)
         .ok()
@@ -444,55 +488,3 @@ fn env_bool(name: &str, default: bool) -> bool {
     }
 }
 
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn cli_mode_defaults_to_backfill_when_unset_or_blank() {
-        let none = parse_crawler_mode_str(None, 20).unwrap();
-        assert!(matches!(none, DiscoverMode::Backfill));
-        let blank = parse_crawler_mode_str(Some(""), 20).unwrap();
-        assert!(matches!(blank, DiscoverMode::Backfill));
-    }
-
-    #[test]
-    fn cli_mode_recognizes_backfill_and_incremental() {
-        let backfill = parse_crawler_mode_str(Some("backfill"), 20).unwrap();
-        assert!(matches!(backfill, DiscoverMode::Backfill));
-
-        let incremental = parse_crawler_mode_str(Some("incremental"), 9).unwrap();
-        assert!(matches!(
-            incremental,
-            DiscoverMode::Incremental { stop_after_unchanged: 9 }
-        ));
-    }
-
-    #[test]
-    fn cli_mode_rejects_auto_explicitly() {
-        let err = parse_crawler_mode_str(Some("auto"), 20).unwrap_err();
-        let msg = format!("{err}");
-        assert!(
-            msg.contains("daemon"),
-            "rejection should point operator at the daemon: {msg}"
-        );
-    }
-
-    #[test]
-    fn cli_mode_rejects_unknown_value() {
-        let err = parse_crawler_mode_str(Some("garbage"), 20).unwrap_err();
-        let msg = format!("{err}");
-        assert!(msg.contains("backfill"));
-        assert!(msg.contains("incremental"));
-    }
-
-    #[test]
-    fn cli_mode_is_case_insensitive_and_trims() {
-        let mixed = parse_crawler_mode_str(Some("  Incremental  "), 4).unwrap();
-        assert!(matches!(
-            mixed,
-            DiscoverMode::Incremental { stop_after_unchanged: 4 }
-        ));
-    }
-}
-

backend/src/config.rs

@@ -5,22 +5,28 @@ use chrono::NaiveTime;
 use chrono_tz::Tz;
 
 use crate::crawler::browser::LaunchOptions;
-use crate::crawler::source::DiscoverMode;
-
-/// What `CRAWLER_MODE` was set to. `Auto` is the daemon's default —
-/// pick Backfill until `seed_completed_at` is written, then flip to
-/// Incremental. `Explicit` forces a single mode regardless.
-#[derive(Clone, Copy, Debug)]
-pub enum CrawlerModePref {
-    Auto,
-    Explicit(DiscoverMode),
-}
+use crate::crawler::safety::{DownloadAllowlist, DEFAULT_MAX_IMAGE_BYTES};
 
 #[derive(Clone, Debug)]
 pub struct AuthConfig {
     pub cookie_secure: bool,
     pub cookie_domain: Option<String>,
     pub session_ttl_days: i64,
+    pub rate_limit: crate::auth::rate_limit::RateLimitConfig,
+    /// When `false`, `POST /auth/register` returns 403
+    /// `registration_disabled` and the frontend hides its register
+    /// affordance. Admins can still mint accounts via
+    /// `POST /admin/users`. Defaults to `true` (open registration)
+    /// for backward compatibility.
+    pub allow_self_register: bool,
+    /// When `true`, every API path except a small allowlist
+    /// (`/health`, `/auth/config`, `/auth/login`, `/auth/logout`)
+    /// requires a valid session cookie or bearer token — anonymous
+    /// reads are rejected with 401. Self-registration is also
+    /// force-disabled regardless of [`Self::allow_self_register`]
+    /// so a private instance is locked down with a single switch.
+    /// Defaults to `false` (current public behaviour).
+    pub private_mode: bool,
 }
 
 impl Default for AuthConfig {
@@ -29,6 +35,13 @@ impl Default for AuthConfig {
             cookie_secure: true,
             cookie_domain: None,
             session_ttl_days: 30,
+            // Disabled by default so the test harness inherits a
+            // non-throttling limiter. Production `from_env` overrides
+            // to the [`PRODUCTION_PER_SEC`]/[`PRODUCTION_BURST`]
+            // defaults.
+            rate_limit: crate::auth::rate_limit::RateLimitConfig::default(),
+            allow_self_register: true,
+            private_mode: false,
         }
     }
 }
@@ -62,6 +75,13 @@ pub struct Config {
     pub upload: UploadConfig,
     pub cors_allowed_origins: Vec<String>,
     pub crawler: CrawlerConfig,
+    /// `(username, password)` for the admin user provisioned at startup
+    /// when both `ADMIN_USERNAME` and `ADMIN_PASSWORD` are set. `None`
+    /// skips the bootstrap entirely. See `repo::user::bootstrap_admin`
+    /// for the create-vs-promote semantics — notably the password here
+    /// is used only when creating a new row, never to overwrite an
+    /// existing one.
+    pub admin_bootstrap: Option<(String, String)>,
 }
 
 /// All crawler-daemon knobs read from env. Mirrors the env vars the
@@ -86,13 +106,32 @@ pub struct CrawlerConfig {
     pub cookie_domain: Option<String>,
     pub user_agent: Option<String>,
     pub proxy: Option<String>,
+    /// `tcp://host:port`, `host:port`, or bare `host` (default port
+    /// 9051). When `None`, TOR-recircuit-on-transient is disabled and
+    /// the crawler behaves identically to pre-TOR releases.
+    pub tor_control_url: Option<String>,
+    /// HashedControlPassword auth. Used only when
+    /// `tor_control_cookie_path` is `None`.
+    pub tor_control_password: Option<String>,
+    /// Cookie-file auth path (e.g.
+    /// `/var/lib/tor/control_auth_cookie`). Takes precedence over
+    /// password when both are set.
+    pub tor_control_cookie_path: Option<PathBuf>,
+    /// Maximum NEWNYM-and-retry cycles per recircuit-eligible failure.
+    /// Defaults to 3.
+    pub tor_recircuit_max_attempts: u32,
     pub browser: LaunchOptions,
-    /// Mode preference for the metadata pass. Daemon default is `Auto`
-    /// (Backfill until `seed_completed_at` is written, then Incremental).
-    pub mode: CrawlerModePref,
-    /// `stop_after_unchanged` threshold supplied to Incremental in both
-    /// `Auto` (post-seed) and `Explicit(Incremental)` modes.
-    pub incremental_stop_after: usize,
+    /// Hosts the crawler is allowed to download images / covers from.
+    /// Always seeded with the host of `start_url` and (when set) the
+    /// configured `cdn_host`. Additional hosts can be added via
+    /// `CRAWLER_DOWNLOAD_ALLOWLIST` (comma-separated).
+    pub download_allowlist: DownloadAllowlist,
+    /// Hard upper bound on a single image download. Defaults to 32 MiB.
+    pub max_image_bytes: usize,
+    /// Max manga detail fetches per metadata pass. `0` means no cap
+    /// (full sweep up to the source's own bound). Sourced from
+    /// `CRAWLER_LIMIT`, mirroring the CLI binary.
+    pub manga_limit: usize,
 }
 
 impl Default for CrawlerConfig {
@@ -112,9 +151,14 @@ impl Default for CrawlerConfig {
             cookie_domain: None,
             user_agent: None,
             proxy: None,
+            tor_control_url: None,
+            tor_control_password: None,
+            tor_control_cookie_path: None,
+            tor_recircuit_max_attempts: 3,
             browser: LaunchOptions::headless(),
-            mode: CrawlerModePref::Auto,
-            incremental_stop_after: 20,
+            download_allowlist: DownloadAllowlist::new(),
+            max_image_bytes: DEFAULT_MAX_IMAGE_BYTES,
+            manga_limit: 0,
         }
     }
 }
@@ -135,6 +179,18 @@ impl Config {
                     .ok()
                     .filter(|s| !s.is_empty()),
                 session_ttl_days: env_i64("SESSION_TTL_DAYS", 30),
+                rate_limit: crate::auth::rate_limit::RateLimitConfig {
+                    per_sec: env_u64(
+                        "AUTH_RATE_PER_SEC",
+                        crate::auth::rate_limit::PRODUCTION_PER_SEC.into(),
+                    ) as u32,
+                    burst: env_u64(
+                        "AUTH_RATE_BURST",
+                        crate::auth::rate_limit::PRODUCTION_BURST.into(),
+                    ) as u32,
+                },
+                allow_self_register: env_bool("ALLOW_SELF_REGISTER", true),
+                private_mode: env_bool("PRIVATE_MODE", false),
             },
             upload: UploadConfig {
                 max_request_bytes: env_usize("MAX_REQUEST_BYTES", 200 * 1024 * 1024),
@@ -150,10 +206,21 @@ impl Config {
                 })
                 .unwrap_or_default(),
             crawler: CrawlerConfig::from_env()?,
+            admin_bootstrap: admin_bootstrap_from_env(),
         })
     }
 }
 
+/// Returns `Some((username, password))` only when BOTH `ADMIN_USERNAME`
+/// and `ADMIN_PASSWORD` are set and non-empty. Half-set configuration is
+/// treated as "no bootstrap" rather than a hard error, so an operator
+/// can comment out one env var without crashing the server.
+fn admin_bootstrap_from_env() -> Option<(String, String)> {
+    let username = std::env::var("ADMIN_USERNAME").ok().filter(|s| !s.is_empty())?;
+    let password = std::env::var("ADMIN_PASSWORD").ok().filter(|s| !s.is_empty())?;
+    Some((username, password))
+}
+
 impl CrawlerConfig {
     pub fn from_env() -> anyhow::Result<Self> {
         // Parse CRAWLER_DAILY_AT (HH:MM, 24h). Invalid → fail fast.
@@ -169,9 +236,14 @@ impl CrawlerConfig {
                 .parse()
                 .map_err(|e| anyhow::anyhow!("CRAWLER_TZ must be a valid IANA TZ (got {raw:?}): {e}"))?,
         };
-        let incremental_stop_after =
-            env_u64("CRAWLER_INCREMENTAL_STOP_AFTER", 20).max(1) as usize;
-        let mode = parse_mode_env(incremental_stop_after)?;
+        let start_url = std::env::var("CRAWLER_START_URL")
+            .ok()
+            .filter(|s| !s.trim().is_empty());
+        let cdn_host = std::env::var("CRAWLER_CDN_HOST")
+            .ok()
+            .filter(|s| !s.trim().is_empty());
+        let download_allowlist =
+            build_download_allowlist(start_url.as_deref(), cdn_host.as_deref());
         Ok(Self {
             daemon_enabled: env_bool("CRAWLER_DAEMON", true),
             daily_at,
@@ -179,13 +251,9 @@ impl CrawlerConfig {
             idle_timeout: Duration::from_secs(env_u64("CRAWLER_IDLE_TIMEOUT_S", 600)),
             chapter_workers: env_u64("CRAWLER_CHAPTER_WORKERS", 1).max(1) as usize,
             retention_days: env_u64("CRAWLER_JOB_RETENTION_DAYS", 7) as u32,
-            start_url: std::env::var("CRAWLER_START_URL")
-                .ok()
-                .filter(|s| !s.trim().is_empty()),
+            start_url,
             rate_ms: env_u64("CRAWLER_RATE_MS", 1000),
-            cdn_host: std::env::var("CRAWLER_CDN_HOST")
-                .ok()
-                .filter(|s| !s.trim().is_empty()),
+            cdn_host,
             cdn_rate_ms: env_u64("CRAWLER_CDN_RATE_MS", env_u64("CRAWLER_RATE_MS", 1000)),
             phpsessid: std::env::var("CRAWLER_PHPSESSID")
                 .ok()
@@ -199,37 +267,64 @@ impl CrawlerConfig {
             proxy: std::env::var("CRAWLER_PROXY")
                 .ok()
                 .filter(|s| !s.trim().is_empty()),
+            tor_control_url: std::env::var("CRAWLER_TOR_CONTROL_URL")
+                .ok()
+                .filter(|s| !s.trim().is_empty()),
+            tor_control_password: std::env::var("CRAWLER_TOR_CONTROL_PASSWORD")
+                .ok()
+                .filter(|s| !s.trim().is_empty()),
+            tor_control_cookie_path: std::env::var("CRAWLER_TOR_CONTROL_COOKIE_PATH")
+                .ok()
+                .filter(|s| !s.trim().is_empty())
+                .map(PathBuf::from),
+            tor_recircuit_max_attempts: env_u64("CRAWLER_TOR_RECIRCUIT_MAX_ATTEMPTS", 3)
+                .max(1) as u32,
             browser: LaunchOptions::from_env(),
-            mode,
-            incremental_stop_after,
+            download_allowlist,
+            max_image_bytes: env_usize("CRAWLER_MAX_IMAGE_BYTES", DEFAULT_MAX_IMAGE_BYTES),
+            manga_limit: env_usize("CRAWLER_LIMIT", 0),
         })
     }
 }
 
-/// Parse `CRAWLER_MODE`. Empty/unset → `Auto`. Recognized values are
-/// `auto`, `backfill`, and `incremental` (case-insensitive). Anything
-/// else is a hard error so a typo can't silently fall through to the
-/// default and mask itself.
-fn parse_mode_env(incremental_stop_after: usize) -> anyhow::Result<CrawlerModePref> {
-    parse_mode_str(std::env::var("CRAWLER_MODE").ok().as_deref(), incremental_stop_after)
-}
-
-/// Pure variant of [`parse_mode_env`] — testable without env-var
-/// mutation. Takes the raw value (or `None` if unset).
-pub(crate) fn parse_mode_str(
-    raw: Option<&str>,
-    incremental_stop_after: usize,
-) -> anyhow::Result<CrawlerModePref> {
-    match raw.map(|s| s.trim().to_ascii_lowercase()).as_deref() {
-        None | Some("") | Some("auto") => Ok(CrawlerModePref::Auto),
-        Some("backfill") => Ok(CrawlerModePref::Explicit(DiscoverMode::Backfill)),
-        Some("incremental") => Ok(CrawlerModePref::Explicit(DiscoverMode::Incremental {
-            stop_after_unchanged: incremental_stop_after,
-        })),
-        Some(other) => Err(anyhow::anyhow!(
-            "CRAWLER_MODE must be one of: auto, backfill, incremental (got {other:?})"
-        )),
+/// Build the download allowlist from env. Always includes
+/// `CRAWLER_START_URL`'s host (so the crawler can fetch covers from
+/// the catalog itself) and `CRAWLER_CDN_HOST` when set. Additional
+/// hosts can be supplied via `CRAWLER_DOWNLOAD_ALLOWLIST` (comma-
+/// separated). Empty by default — meaning the crawler refuses to
+/// download anything when no source is configured, which is the safe
+/// fail-closed posture.
+///
+/// `CRAWLER_ALLOW_ANY_HOST=true` short-circuits the host enumeration
+/// for operators whose sources shard across numbered CDN subdomains.
+/// Scheme + private-IP defenses still apply.
+fn build_download_allowlist(
+    start_url: Option<&str>,
+    cdn_host: Option<&str>,
+) -> DownloadAllowlist {
+    if env_bool("CRAWLER_ALLOW_ANY_HOST", false) {
+        return DownloadAllowlist::allow_any();
     }
+    let mut allow = DownloadAllowlist::new();
+    if let Some(url) = start_url {
+        if let Ok(parsed) = reqwest::Url::parse(url) {
+            if let Some(h) = parsed.host_str() {
+                allow = allow.allow(h);
+            }
+        }
+    }
+    if let Some(host) = cdn_host {
+        allow = allow.allow(host);
+    }
+    if let Ok(extras) = std::env::var("CRAWLER_DOWNLOAD_ALLOWLIST") {
+        for piece in extras.split(',') {
+            let trimmed = piece.trim();
+            if !trimmed.is_empty() {
+                allow = allow.allow(trimmed);
+            }
+        }
+    }
+    allow
 }
 
 fn env_u64(name: &str, default: u64) -> u64 {
@@ -264,59 +359,61 @@ fn env_usize(name: &str, default: usize) -> usize {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use std::sync::Mutex;
+
+    // Serialise env-touching tests so concurrent cargo-test threads don't
+    // race on the process-global env. Re-acquire on poison since a
+    // panicking test still leaves the env in a consistent state for us
+    // (we set/unset within each guard region).
+    static ENV_GUARD: Mutex<()> = Mutex::new(());
 
     #[test]
-    fn parse_mode_str_defaults_to_auto_when_unset_or_blank() {
-        let none = parse_mode_str(None, 20).unwrap();
-        assert!(matches!(none, CrawlerModePref::Auto));
-        let blank = parse_mode_str(Some(""), 20).unwrap();
-        assert!(matches!(blank, CrawlerModePref::Auto));
-        let whitespace = parse_mode_str(Some("   "), 20).unwrap();
-        assert!(matches!(whitespace, CrawlerModePref::Auto));
+    fn crawler_limit_env_populates_manga_limit() {
+        let _g = ENV_GUARD.lock().unwrap_or_else(|p| p.into_inner());
+        std::env::set_var("CRAWLER_LIMIT", "96");
+        let cfg = CrawlerConfig::from_env().expect("from_env");
+        std::env::remove_var("CRAWLER_LIMIT");
+        assert_eq!(cfg.manga_limit, 96);
     }
 
     #[test]
-    fn parse_mode_str_recognizes_each_keyword() {
-        let auto = parse_mode_str(Some("auto"), 20).unwrap();
-        assert!(matches!(auto, CrawlerModePref::Auto));
-
-        let backfill = parse_mode_str(Some("backfill"), 20).unwrap();
-        assert!(matches!(
-            backfill,
-            CrawlerModePref::Explicit(DiscoverMode::Backfill)
-        ));
-
-        let incremental = parse_mode_str(Some("incremental"), 7).unwrap();
-        assert!(matches!(
-            incremental,
-            CrawlerModePref::Explicit(DiscoverMode::Incremental {
-                stop_after_unchanged: 7
-            })
-        ));
+    fn crawler_limit_unset_defaults_to_zero() {
+        let _g = ENV_GUARD.lock().unwrap_or_else(|p| p.into_inner());
+        std::env::remove_var("CRAWLER_LIMIT");
+        let cfg = CrawlerConfig::from_env().expect("from_env");
+        assert_eq!(cfg.manga_limit, 0);
     }
 
     #[test]
-    fn parse_mode_str_is_case_insensitive_and_trims_whitespace() {
-        let mixed = parse_mode_str(Some("  Incremental  "), 5).unwrap();
-        assert!(matches!(
-            mixed,
-            CrawlerModePref::Explicit(DiscoverMode::Incremental {
-                stop_after_unchanged: 5
-            })
-        ));
-        let upper = parse_mode_str(Some("BACKFILL"), 5).unwrap();
-        assert!(matches!(
-            upper,
-            CrawlerModePref::Explicit(DiscoverMode::Backfill)
-        ));
+    fn private_mode_env_parses_true() {
+        let _g = ENV_GUARD.lock().unwrap_or_else(|p| p.into_inner());
+        std::env::set_var("PRIVATE_MODE", "true");
+        std::env::set_var("DATABASE_URL", "postgres://test");
+        let cfg = Config::from_env().expect("from_env");
+        std::env::remove_var("PRIVATE_MODE");
+        std::env::remove_var("DATABASE_URL");
+        assert!(cfg.auth.private_mode);
     }
 
     #[test]
-    fn parse_mode_str_hard_errors_on_unknown_value() {
-        let err = parse_mode_str(Some("backfil"), 20).unwrap_err();
-        let msg = format!("{err}");
-        assert!(msg.contains("backfill"), "error should list valid values: {msg}");
-        assert!(msg.contains("auto"));
-        assert!(msg.contains("incremental"));
+    fn private_mode_env_parses_false() {
+        let _g = ENV_GUARD.lock().unwrap_or_else(|p| p.into_inner());
+        std::env::set_var("PRIVATE_MODE", "false");
+        std::env::set_var("DATABASE_URL", "postgres://test");
+        let cfg = Config::from_env().expect("from_env");
+        std::env::remove_var("PRIVATE_MODE");
+        std::env::remove_var("DATABASE_URL");
+        assert!(!cfg.auth.private_mode);
+    }
+
+    #[test]
+    fn private_mode_defaults_to_false() {
+        let _g = ENV_GUARD.lock().unwrap_or_else(|p| p.into_inner());
+        std::env::remove_var("PRIVATE_MODE");
+        std::env::set_var("DATABASE_URL", "postgres://test");
+        let cfg = Config::from_env().expect("from_env");
+        std::env::remove_var("DATABASE_URL");
+        assert!(!cfg.auth.private_mode);
     }
 }
+

backend/src/crawler/browser.rs

@@ -1,10 +1,17 @@
 //! Chromium launcher and lifecycle.
 //!
-//! Uses `chromiumoxide`'s `fetcher` feature so we don't depend on a
-//! system Chrome install — first call downloads a known-good revision
-//! into a cache dir and reuses it forever after. `BrowserMode` toggles
-//! headed vs headless; the headed path needs a display (real `$DISPLAY`
-//! or `xvfb-run`).
+//! By default uses `chromiumoxide`'s `fetcher` feature — first call
+//! downloads a known-good revision into a cache dir and reuses it
+//! forever after. Set `CRAWLER_CHROMIUM_BINARY` to skip the fetcher
+//! and use a system-installed Chromium instead; required on platforms
+//! where the upstream snapshot bucket has no usable build (notably
+//! `Linux_arm64` / Raspberry Pi). Debian's package is at
+//! `/usr/bin/chromium` or `/usr/bin/chromium-headless-shell`; Ubuntu
+//! ships it as `chromium-browser` at a different path — don't paste
+//! the wrong one.
+//!
+//! `BrowserMode` toggles headed vs headless; the headed path needs a
+//! display (real `$DISPLAY` or `xvfb-run`).
 //!
 //! Extra Chromium command-line flags can be supplied through
 //! [`LaunchOptions::extra_args`] in code, or via the
@@ -121,54 +128,85 @@ impl Handle {
     }
 
     /// Closes the browser and awaits the driver task. If other Arcs to
-    /// the browser are still alive we fall back to drop-kills-Chromium
-    /// semantics and just join the driver — this is the rare case where
-    /// shutdown raced an outstanding worker; the OS-level kill is the
-    /// safety net.
+    /// the browser are still alive we can't issue a clean CDP `close`,
+    /// so we abort the driver task instead — otherwise `handler.next()`
+    /// keeps polling forever and `Handle::close` hangs (chromiumoxide's
+    /// handler stream doesn't end on its own when the underlying WS
+    /// dies). Chromium itself is reaped by kill-on-drop once the last
+    /// `Arc<Browser>` is dropped.
     pub async fn close(self) -> anyhow::Result<()> {
-        match Arc::try_unwrap(self.browser) {
-            Ok(mut owned) => {
-                let _ = owned.close().await;
-                let _ = owned.wait().await;
-            }
-            Err(shared) => {
-                tracing::warn!(
-                    strong_count = Arc::strong_count(&shared),
-                    "Handle::close while Arc<Browser> still shared — relying on kill-on-drop"
-                );
-                drop(shared);
-            }
-        }
-        let _ = self.driver.await;
+        close_or_abort(self.browser, self.driver, |mut owned| async move {
+            let _ = owned.close().await;
+            let _ = owned.wait().await;
+        })
+        .await;
         Ok(())
     }
 }
 
-/// Launches Chromium. Downloads it on first run via the `fetcher`
-/// feature; subsequent runs hit the cache. The cache dir is
+/// Shutdown core for [`Handle::close`], extracted so it can be unit-
+/// tested without launching real Chromium. When `arc` is uniquely owned,
+/// `on_owned` runs against the owned value and the driver is awaited
+/// normally. When other Arc holders exist, the driver is aborted before
+/// awaiting it so shutdown returns promptly.
+async fn close_or_abort<T, F, Fut>(arc: Arc<T>, driver: JoinHandle<()>, on_owned: F)
+where
+    T: Send + 'static,
+    F: FnOnce(T) -> Fut + Send,
+    Fut: std::future::Future<Output = ()> + Send,
+{
+    match Arc::try_unwrap(arc) {
+        Ok(owned) => {
+            on_owned(owned).await;
+            let _ = driver.await;
+        }
+        Err(shared) => {
+            tracing::warn!(
+                strong_count = Arc::strong_count(&shared),
+                "Handle::close while Arc still shared — aborting driver, relying on kill-on-drop"
+            );
+            drop(shared);
+            driver.abort();
+            let _ = driver.await;
+        }
+    }
+}
+
+/// Launches Chromium. If `CRAWLER_CHROMIUM_BINARY` is set, uses that
+/// path directly. Otherwise downloads via the `fetcher` feature on
+/// first run and hits the cache after that. The fetcher cache dir is
 /// `$CRAWLER_CHROMIUM_DIR` if set, else `$HOME/.cache/mangalord/chromium`,
 /// else `./.chromium-cache` as a last-resort repo-local fallback.
 pub async fn launch(options: LaunchOptions) -> anyhow::Result<Handle> {
-    let cache = cache_dir()?;
-    tokio::fs::create_dir_all(&cache)
-        .await
-        .with_context(|| format!("create cache dir {}", cache.display()))?;
+    let executable = match system_chromium_path_from_env() {
+        Some(path) => {
+            tracing::info!(path = %path.display(), "using system chromium (CRAWLER_CHROMIUM_BINARY)");
+            path
+        }
+        None => {
+            let cache = cache_dir()?;
+            tokio::fs::create_dir_all(&cache)
+                .await
+                .with_context(|| format!("create cache dir {}", cache.display()))?;
 
-    let fetcher = BrowserFetcher::new(
-        BrowserFetcherOptions::builder()
-            .with_path(&cache)
-            .build()
-            .map_err(|e| anyhow::anyhow!("fetcher options: {e}"))?,
-    );
-    tracing::info!(path = %cache.display(), "ensuring chromium revision is present");
-    let info = fetcher
-        .fetch()
-        .await
-        .context("download chromium via fetcher")?;
-    tracing::info!(executable = %info.executable_path.display(), "chromium ready");
+            let fetcher = BrowserFetcher::new(
+                BrowserFetcherOptions::builder()
+                    .with_path(&cache)
+                    .build()
+                    .map_err(|e| anyhow::anyhow!("fetcher options: {e}"))?,
+            );
+            tracing::info!(path = %cache.display(), "ensuring chromium revision is present");
+            let info = fetcher
+                .fetch()
+                .await
+                .context("download chromium via fetcher")?;
+            tracing::info!(executable = %info.executable_path.display(), "chromium ready");
+            info.executable_path
+        }
+    };
 
     let mut builder = BrowserConfig::builder()
-        .chrome_executable(info.executable_path)
+        .chrome_executable(executable)
         // Linux containers / CI commonly lack the user namespaces
         // Chromium's sandbox wants. Disable it; the crawler runs in its
         // own container anyway.
@@ -225,6 +263,24 @@ fn cache_dir() -> anyhow::Result<PathBuf> {
     Ok(PathBuf::from("./.chromium-cache"))
 }
 
+/// Reads `CRAWLER_CHROMIUM_BINARY` and delegates to the pure helper.
+/// Thin wrapper kept separate so the decision logic can be unit-tested
+/// without mutating the process environment.
+fn system_chromium_path_from_env() -> Option<PathBuf> {
+    system_chromium_path_from_value(std::env::var_os("CRAWLER_CHROMIUM_BINARY").as_deref())
+}
+
+/// Returns `Some(path)` only when the value is set and non-empty. An
+/// exported-but-blank var (common in compose `${VAR:-}` patterns when
+/// the operator didn't fill it in) must behave like "unset" — otherwise
+/// we'd hand chromiumoxide an empty path and fail launch in a confusing
+/// way.
+pub(crate) fn system_chromium_path_from_value(
+    raw: Option<&std::ffi::OsStr>,
+) -> Option<PathBuf> {
+    raw.filter(|v| !v.is_empty()).map(PathBuf::from)
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -252,6 +308,33 @@ mod tests {
         assert!(parse_args("   \t\n").is_empty());
     }
 
+    #[test]
+    fn system_chromium_path_returns_some_when_value_set() {
+        let raw = std::ffi::OsString::from("/usr/bin/chromium-headless-shell");
+        assert_eq!(
+            system_chromium_path_from_value(Some(raw.as_os_str())),
+            Some(PathBuf::from("/usr/bin/chromium-headless-shell"))
+        );
+    }
+
+    #[test]
+    fn system_chromium_path_returns_none_when_unset() {
+        assert_eq!(system_chromium_path_from_value(None), None);
+    }
+
+    #[test]
+    fn system_chromium_path_treats_empty_as_unset() {
+        // Compose's `${VAR:-}` substitution produces an exported-but-empty
+        // env var when the operator left it blank. Treat it as unset so
+        // the launcher falls back to the fetcher path instead of handing
+        // chromiumoxide an empty path.
+        let raw = std::ffi::OsString::from("");
+        assert_eq!(
+            system_chromium_path_from_value(Some(raw.as_os_str())),
+            None
+        );
+    }
+
     #[test]
     fn default_launch_options_are_headless() {
         // Headless is the production-safe default — no display required,
@@ -261,4 +344,54 @@ mod tests {
         assert_eq!(LaunchOptions::headless().mode, BrowserMode::Headless);
         assert_eq!(LaunchOptions::headed().mode, BrowserMode::Headed);
     }
+
+    // Regression: if another Arc<Browser> outlives `Handle::close`, the
+    // old code awaited the driver task forever because the chromiumoxide
+    // handler stream doesn't return None on its own. Aborting the driver
+    // unblocks shutdown even when kill-on-drop can't fire yet.
+    #[tokio::test]
+    async fn close_or_abort_returns_when_arc_is_shared() {
+        use std::sync::atomic::{AtomicBool, Ordering};
+        use std::time::Duration;
+
+        let arc = Arc::new(());
+        let _keepalive = Arc::clone(&arc); // forces try_unwrap to fail
+        let driver = tokio::spawn(std::future::pending::<()>());
+        let on_owned_ran = Arc::new(AtomicBool::new(false));
+
+        let flag = Arc::clone(&on_owned_ran);
+        let fut = close_or_abort(arc, driver, move |_| {
+            let flag = Arc::clone(&flag);
+            async move { flag.store(true, Ordering::Release) }
+        });
+
+        tokio::time::timeout(Duration::from_secs(2), fut)
+            .await
+            .expect("close_or_abort must not hang when driver is pending and Arc is shared");
+        assert!(
+            !on_owned_ran.load(Ordering::Acquire),
+            "on_owned must not run when the Arc is still shared"
+        );
+    }
+
+    #[tokio::test]
+    async fn close_or_abort_runs_on_owned_when_arc_is_unique() {
+        use std::sync::atomic::{AtomicBool, Ordering};
+
+        let arc = Arc::new(());
+        let driver = tokio::spawn(async {}); // completes immediately
+        let on_owned_ran = Arc::new(AtomicBool::new(false));
+
+        let flag = Arc::clone(&on_owned_ran);
+        close_or_abort(arc, driver, move |_| {
+            let flag = Arc::clone(&flag);
+            async move { flag.store(true, Ordering::Release) }
+        })
+        .await;
+
+        assert!(
+            on_owned_ran.load(Ordering::Acquire),
+            "on_owned must run when the Arc is unique"
+        );
+    }
 }

backend/src/crawler/browser_manager.rs

@@ -145,6 +145,28 @@ impl BrowserManager {
         }
     }
 
+    /// Mark the cached browser handle as unhealthy. The next `acquire`
+    /// will re-launch Chromium from scratch.
+    ///
+    /// Same semantics as `shutdown` — the difference is intent:
+    /// `shutdown` runs once at daemon teardown, while `invalidate` is a
+    /// recovery hook callers fire after a CDP / connection / navigation
+    /// failure that suggests the underlying process has died. Calling
+    /// this while other workers still hold leases is safe — their
+    /// outstanding CDP operations will return channel-closed errors
+    /// and those workers will then re-acquire (re-launching Chromium).
+    ///
+    /// Idempotent: calling on an already-invalidated manager is a
+    /// no-op.
+    pub async fn invalidate(&self) {
+        let mut guard = self.inner.lock().await;
+        guard.shared = None;
+        if let Some(handle) = guard.handle.take() {
+            let _ = handle.close().await;
+            tracing::warn!("BrowserManager: handle invalidated — next acquire will relaunch");
+        }
+    }
+
     fn idle_timeout(&self) -> Duration {
         self.idle_timeout
     }
@@ -231,6 +253,23 @@ mod tests {
         assert_send_sync(&h);
     }
 
+    /// Invalidate is the only `BrowserManager` method that's safe to
+    /// exercise in a unit test without launching Chromium — it's a
+    /// no-op when no handle has been cached, and that path is exactly
+    /// the one we want to verify is idempotent.
+    #[tokio::test]
+    async fn invalidate_is_a_noop_when_no_handle_cached() {
+        let mgr = BrowserManager::new(
+            crate::crawler::browser::LaunchOptions::default(),
+            Duration::ZERO,
+            noop_on_launch(),
+        );
+        // Two back-to-back invalidates must both complete; the second
+        // would hang or panic if the first had left torn state.
+        mgr.invalidate().await;
+        mgr.invalidate().await;
+    }
+
     #[tokio::test]
     async fn active_tracker_signals_idle_only_on_zero_transition() {
         let tracker = ActiveTracker::new();

backend/src/crawler/content.rs

@@ -18,7 +18,8 @@ use uuid::Uuid;
 
 use crate::crawler::detect::PageError;
 use crate::crawler::rate_limit::HostRateLimiters;
-use crate::crawler::session;
+use crate::crawler::safety::{fetch_bytes_capped, looks_like_image, DownloadAllowlist};
+use crate::crawler::session::{self, ChapterProbe};
 use crate::storage::Storage;
 
 /// Parse the chapter page DOM and return the page images in `pageN`
@@ -72,6 +73,119 @@ pub enum SyncOutcome {
     SessionExpired,
 }
 
+/// Per-chapter max fetch attempts when TOR is configured. `N = 3` means
+/// up to 3 total page fetches with 2 NEWNYM signals between them. When
+/// TOR is not configured the effective budget collapses to 1 (single
+/// attempt, no retry, no recircuit — bit-for-bit pre-TOR behavior).
+const CHAPTER_RECIRCUIT_MAX_ATTEMPTS: u32 = 3;
+
+/// Outcome of [`fetch_chapter_html_with_recircuit`]. `Ok` carries the
+/// final reader HTML; the other two map to `sync_chapter_content`'s
+/// existing failure modes.
+#[derive(Debug)]
+enum ChapterFetchOutcome {
+    Ok(String),
+    /// `ChapterProbe::Unauthenticated` after exhausting recircuit
+    /// budget (or with budget=0). Caller returns
+    /// `SyncOutcome::SessionExpired`.
+    SessionExpired,
+    /// `ChapterProbe::Transient` after exhausting recircuit budget
+    /// (or with budget=0). Caller bails so the dispatcher does
+    /// exponential backoff.
+    PersistentTransient,
+}
+
+/// Single rate-limited Chromium navigation to the chapter URL,
+/// returning the page HTML. Extracted from `sync_chapter_content` so
+/// the recircuit loop can call it once per attempt.
+async fn fetch_chapter_html_once(
+    browser: &chromiumoxide::Browser,
+    rate: &HostRateLimiters,
+    source_url: &str,
+) -> anyhow::Result<String> {
+    rate.wait_for(source_url).await?;
+    let page = browser
+        .new_page(source_url)
+        .await
+        .with_context(|| format!("open chapter page {source_url}"))?;
+    crate::crawler::nav::wait_for_nav(&page)
+        .await
+        .context("wait for chapter nav")?;
+    // Best-effort wait for the reader marker — same partial-render
+    // race that bit the chapter-list parser can hit here. Timeout is
+    // not an error; the chapter probe + parser sentinels still catch
+    // real failures.
+    let _ = crate::crawler::nav::wait_for_selector(
+        &page,
+        "a#pic_container",
+        crate::crawler::nav::SELECTOR_TIMEOUT,
+    )
+    .await;
+    let html = page.content().await.context("read chapter html")?;
+    page.close().await.ok();
+    Ok(html)
+}
+
+/// Pure-over-IO loop: fetch + classify, up to `max_attempts` total
+/// fetches. Between attempts, `recircuit` is invoked (a no-op when
+/// TOR isn't configured). `max_attempts = 1` collapses to the
+/// original single-shot behavior — `Unauthenticated` →
+/// `SessionExpired`, `Transient` → `PersistentTransient` on the first
+/// hit, no recircuit.
+///
+/// Semantics match [`crate::crawler::detect::retry_on_transient`] and
+/// [`run_session_probe_loop`]: `N` is **total attempts including the
+/// first**, so `N = 3` means 3 fetches and up to 2 NEWNYM calls.
+/// `Unauthenticated` and `Transient` share the budget — the loop
+/// doesn't distinguish, so a sequence like Transient → Unauth → Ok
+/// counts as 3 attempts.
+async fn fetch_chapter_html_with_recircuit<F, Fut, R, RFut>(
+    mut fetch: F,
+    mut recircuit: R,
+    max_attempts: u32,
+    source_url_for_msg: &str,
+) -> anyhow::Result<ChapterFetchOutcome>
+where
+    F: FnMut() -> Fut,
+    Fut: std::future::Future<Output = anyhow::Result<String>>,
+    R: FnMut() -> RFut,
+    RFut: std::future::Future<Output = ()>,
+{
+    debug_assert!(max_attempts >= 1, "max_attempts must be at least 1");
+    let mut attempt = 0u32;
+    loop {
+        attempt += 1;
+        let html = fetch().await?;
+        match session::classify_chapter_probe(&html) {
+            ChapterProbe::Ok => return Ok(ChapterFetchOutcome::Ok(html)),
+            ChapterProbe::Unauthenticated => {
+                if attempt >= max_attempts {
+                    return Ok(ChapterFetchOutcome::SessionExpired);
+                }
+                tracing::warn!(
+                    attempt,
+                    max = max_attempts,
+                    url = source_url_for_msg,
+                    "chapter probe Unauthenticated; signaling TOR NEWNYM and retrying"
+                );
+                recircuit().await;
+            }
+            ChapterProbe::Transient => {
+                if attempt >= max_attempts {
+                    return Ok(ChapterFetchOutcome::PersistentTransient);
+                }
+                tracing::warn!(
+                    attempt,
+                    max = max_attempts,
+                    url = source_url_for_msg,
+                    "chapter probe Transient; signaling TOR NEWNYM and retrying"
+                );
+                recircuit().await;
+            }
+        }
+    }
+}
+
 /// Fetch all images for one chapter and persist them atomically. On
 /// any error after the first storage put, the DB transaction rolls
 /// back so the chapter stays at `page_count = 0` and is retried on the
@@ -88,6 +202,9 @@ pub async fn sync_chapter_content(
     manga_id: Uuid,
     source_url: &str,
     force_refetch: bool,
+    allowlist: &DownloadAllowlist,
+    max_image_bytes: usize,
+    tor: Option<&crate::crawler::tor::TorController>,
 ) -> anyhow::Result<SyncOutcome> {
     // Skip if already fetched, unless caller explicitly forces.
     if !force_refetch {
@@ -102,23 +219,37 @@ pub async fn sync_chapter_content(
         }
     }
 
-    // Nav to chapter page (rate-limited per host).
-    rate.wait_for(source_url).await?;
-    let page = browser
-        .new_page(source_url)
-        .await
-        .with_context(|| format!("open chapter page {source_url}"))?;
-    page.wait_for_navigation().await.context("wait for chapter nav")?;
-
-    // Session probe: avatar present == still logged in. Missing means
-    // PHPSESSID expired; bail the entire crawler run.
-    if page.find_element("#avatar_menu").await.is_err() {
-        page.close().await.ok();
-        return Ok(SyncOutcome::SessionExpired);
-    }
-
-    let html = page.content().await.context("read chapter html")?;
-    page.close().await.ok();
+    // Fetch + classify. With TOR configured, allow up to
+    // CHAPTER_RECIRCUIT_MAX_ATTEMPTS total page fetches with NEWNYM
+    // between each. Without TOR, collapse to 1 attempt (no retry, no
+    // recircuit) — matches the pre-TOR single-shot behavior bit-for-bit.
+    let max_attempts = if tor.is_some() { CHAPTER_RECIRCUIT_MAX_ATTEMPTS } else { 1 };
+    let html = match fetch_chapter_html_with_recircuit(
+        || fetch_chapter_html_once(browser, rate, source_url),
+        || async {
+            if let Some(t) = tor {
+                if let Err(e) = t.new_identity().await {
+                    tracing::warn!(error = %e, "TOR NEWNYM failed; continuing with same circuit");
+                }
+            }
+        },
+        max_attempts,
+        source_url,
+    )
+    .await?
+    {
+        ChapterFetchOutcome::Ok(html) => html,
+        ChapterFetchOutcome::SessionExpired => return Ok(SyncOutcome::SessionExpired),
+        ChapterFetchOutcome::PersistentTransient => {
+            // Surface as a typed Err so the dispatcher path runs
+            // ack_failed with exponential backoff (rather than the
+            // session-expired sticky flag).
+            anyhow::bail!(
+                "chapter page at {source_url} returned a transient response after \
+                 {max_attempts} attempt(s); will retry"
+            );
+        }
+    };
 
     let images = parse_chapter_pages(&html)
         .with_context(|| format!("parse chapter pages at {source_url}"))?;
@@ -138,18 +269,29 @@ pub async fn sync_chapter_content(
             format!("join image URL {} onto {source_url}", img.url)
         })?;
         rate.wait_for(url.as_str()).await?;
-        let resp = http
-            .get(url.clone())
-            // Source CDNs commonly check Referer. Set it to the
-            // chapter page — matches what the browser would send.
-            .header(reqwest::header::REFERER, source_url)
-            .send()
-            .await
-            .with_context(|| format!("GET {url}"))?
-            .error_for_status()
-            .with_context(|| format!("non-2xx for {url}"))?;
-        let bytes = resp.bytes().await.context("read image body")?.to_vec();
-        let ext = infer::get(&bytes).map(|k| k.extension()).unwrap_or("bin");
+        let bytes = fetch_bytes_capped(
+            http,
+            url.as_str(),
+            Some(source_url),
+            allowlist,
+            max_image_bytes,
+        )
+        .await?
+        .to_vec();
+        // Reject any non-image response: the only valid output of an
+        // image URL is an image. `infer` returns None on truncated
+        // bytes too, which also wants to be a failure not a silent
+        // `.bin` extension.
+        if !looks_like_image(&bytes) {
+            anyhow::bail!(
+                "image URL {url} returned non-image bytes \
+                 (first 16: {:?}); refusing to store as binary blob",
+                &bytes.get(..16.min(bytes.len()))
+            );
+        }
+        let ext = infer::get(&bytes)
+            .map(|k| k.extension())
+            .expect("looks_like_image asserted infer succeeded");
         fetched.push((img.page_number, bytes, ext));
     }
 
@@ -194,8 +336,9 @@ pub async fn sync_chapter_content(
     Ok(SyncOutcome::Fetched { pages: fetched.len() })
 }
 
-// Suppress unused-import warning for `session` until the bin/crawler
-// wiring lands in this branch and uses it through this module.
+// Suppress unused-import warning for `session::registrable_domain`
+// until the bin/crawler wiring lands in this branch and uses it
+// through this module.
 #[allow(dead_code)]
 fn _keep_session_in_scope() {
     let _ = session::registrable_domain;
@@ -265,4 +408,214 @@ mod tests {
         let err = parse_chapter_pages(html).expect_err("expected Transient");
         assert!(err.is_transient(), "got non-transient: {err}");
     }
+
+    // --- fetch_chapter_html_with_recircuit -------------------------------
+
+    const OK_HTML: &str = r#"<html><body><a id="pic_container"><img id="page1" src="x"/></a></body></html>"#;
+    const UNAUTH_HTML: &str = r#"<html><body><header><div id="logo">x</div></header><main>please log in</main></body></html>"#;
+    const TRANSIENT_HTML: &str = "<html><body><p>we're sorry, the request file are not found.</p></body></html>";
+
+    #[tokio::test]
+    async fn recircuit_loop_ok_first_attempt() {
+        let mut recircuits = 0u32;
+        let mut fetches = 0u32;
+        let outcome = fetch_chapter_html_with_recircuit(
+            || {
+                fetches += 1;
+                async { Ok(OK_HTML.to_string()) }
+            },
+            || {
+                recircuits += 1;
+                async {}
+            },
+            3,
+            "https://example/c",
+        )
+        .await
+        .expect("ok");
+        assert!(matches!(outcome, ChapterFetchOutcome::Ok(_)));
+        assert_eq!(fetches, 1);
+        assert_eq!(recircuits, 0);
+    }
+
+    #[tokio::test]
+    async fn recircuit_loop_unauth_with_single_attempt_returns_session_expired() {
+        // max_attempts=1 = TOR disabled, fail-fast on first Unauthenticated.
+        let mut recircuits = 0u32;
+        let mut fetches = 0u32;
+        let outcome = fetch_chapter_html_with_recircuit(
+            || {
+                fetches += 1;
+                async { Ok(UNAUTH_HTML.to_string()) }
+            },
+            || {
+                recircuits += 1;
+                async {}
+            },
+            1,
+            "https://example/c",
+        )
+        .await
+        .expect("ok-result");
+        assert!(matches!(outcome, ChapterFetchOutcome::SessionExpired));
+        assert_eq!(fetches, 1);
+        assert_eq!(recircuits, 0, "no recircuit when budget is 1 (TOR disabled)");
+    }
+
+    #[tokio::test]
+    async fn recircuit_loop_unauth_then_ok_within_budget() {
+        // max_attempts=3 = up to 3 fetches with 2 recircuits between.
+        let mut recircuits = 0u32;
+        let mut fetch_n = 0u32;
+        let outcome = fetch_chapter_html_with_recircuit(
+            || {
+                fetch_n += 1;
+                let n = fetch_n;
+                async move {
+                    if n == 1 {
+                        Ok(UNAUTH_HTML.to_string())
+                    } else {
+                        Ok(OK_HTML.to_string())
+                    }
+                }
+            },
+            || {
+                recircuits += 1;
+                async {}
+            },
+            3,
+            "https://example/c",
+        )
+        .await
+        .expect("ok");
+        assert!(matches!(outcome, ChapterFetchOutcome::Ok(_)));
+        assert_eq!(fetch_n, 2);
+        assert_eq!(recircuits, 1);
+    }
+
+    #[tokio::test]
+    async fn recircuit_loop_unauth_exhausts_budget_returns_session_expired() {
+        let mut recircuits = 0u32;
+        let mut fetch_n = 0u32;
+        let outcome = fetch_chapter_html_with_recircuit(
+            || {
+                fetch_n += 1;
+                async { Ok(UNAUTH_HTML.to_string()) }
+            },
+            || {
+                recircuits += 1;
+                async {}
+            },
+            3,
+            "https://example/c",
+        )
+        .await
+        .expect("ok-result");
+        assert!(matches!(outcome, ChapterFetchOutcome::SessionExpired));
+        assert_eq!(fetch_n, 3, "max_attempts=3 → 3 fetches total");
+        assert_eq!(recircuits, 2, "2 recircuits between 3 fetches");
+    }
+
+    #[tokio::test]
+    async fn recircuit_loop_transient_then_ok_within_budget() {
+        let mut recircuits = 0u32;
+        let mut fetch_n = 0u32;
+        let outcome = fetch_chapter_html_with_recircuit(
+            || {
+                fetch_n += 1;
+                let n = fetch_n;
+                async move {
+                    if n < 3 {
+                        Ok(TRANSIENT_HTML.to_string())
+                    } else {
+                        Ok(OK_HTML.to_string())
+                    }
+                }
+            },
+            || {
+                recircuits += 1;
+                async {}
+            },
+            3,
+            "https://example/c",
+        )
+        .await
+        .expect("ok");
+        assert!(matches!(outcome, ChapterFetchOutcome::Ok(_)));
+        assert_eq!(fetch_n, 3);
+        assert_eq!(recircuits, 2);
+    }
+
+    #[tokio::test]
+    async fn recircuit_loop_transient_exhausts_budget_returns_persistent() {
+        let mut recircuits = 0u32;
+        let mut fetch_n = 0u32;
+        let outcome = fetch_chapter_html_with_recircuit(
+            || {
+                fetch_n += 1;
+                async { Ok(TRANSIENT_HTML.to_string()) }
+            },
+            || {
+                recircuits += 1;
+                async {}
+            },
+            3,
+            "https://example/c",
+        )
+        .await
+        .expect("ok-result");
+        assert!(matches!(outcome, ChapterFetchOutcome::PersistentTransient));
+        assert_eq!(fetch_n, 3, "max_attempts=3 → 3 fetches total");
+        assert_eq!(recircuits, 2, "2 recircuits between 3 fetches");
+    }
+
+    #[tokio::test]
+    async fn recircuit_loop_mixed_transient_then_unauth_then_ok_shares_budget() {
+        // Audit-prompted regression: outcomes share the attempt counter.
+        // Sequence: Transient (attempt 1) → Unauth (attempt 2) → Ok (3).
+        let mut recircuits = 0u32;
+        let mut fetch_n = 0u32;
+        let outcome = fetch_chapter_html_with_recircuit(
+            || {
+                fetch_n += 1;
+                let n = fetch_n;
+                async move {
+                    match n {
+                        1 => Ok(TRANSIENT_HTML.to_string()),
+                        2 => Ok(UNAUTH_HTML.to_string()),
+                        _ => Ok(OK_HTML.to_string()),
+                    }
+                }
+            },
+            || {
+                recircuits += 1;
+                async {}
+            },
+            3,
+            "https://example/c",
+        )
+        .await
+        .expect("ok");
+        assert!(matches!(outcome, ChapterFetchOutcome::Ok(_)));
+        assert_eq!(fetch_n, 3);
+        assert_eq!(recircuits, 2);
+    }
+
+    #[tokio::test]
+    async fn recircuit_loop_propagates_fetch_errors() {
+        let mut fetch_n = 0u32;
+        let err = fetch_chapter_html_with_recircuit(
+            || {
+                fetch_n += 1;
+                async { Err(anyhow::anyhow!("nav timeout")) }
+            },
+            || async {},
+            3,
+            "https://example/c",
+        )
+        .await
+        .expect_err("fetch error bubbles");
+        assert_eq!(fetch_n, 1);
+        assert!(format!("{err:#}").contains("nav timeout"));
+    }
 }

backend/src/crawler/daemon.rs

@@ -233,23 +233,37 @@ impl CronContext {
             return;
         }
 
-        match self.metadata.run().await {
-            Ok(stats) => tracing::info!(?stats, "cron: metadata pass done"),
-            Err(e) => tracing::error!(?e, "cron: metadata pass failed"),
-        }
-
-        match pipeline::enqueue_bookmarked_pending(&self.pool).await {
-            Ok(summary) => tracing::info!(?summary, "cron: enqueued bookmarked-pending"),
-            Err(e) => tracing::error!(?e, "cron: enqueue_bookmarked_pending failed"),
-        }
-
-        match jobs::reap_done(&self.pool, self.retention_days).await {
-            Ok(n) => tracing::info!(reaped = n, "cron: done-job reaper finished"),
-            Err(e) => tracing::error!(?e, "cron: done-job reaper failed"),
-        }
-
-        if let Err(e) = write_last_tick(&self.pool, Utc::now()).await {
-            tracing::warn!(?e, "cron: persist last_metadata_tick_at failed");
+        // Panic-isolate the tick body the same way `process_lease` does
+        // for worker dispatch. Without this, a panic in metadata.run
+        // (or any of the follow-on steps) would kill the cron task and
+        // no future tick would ever run — workers would keep going but
+        // no new metadata work would be scheduled until daemon restart.
+        // The advisory unlock below runs unconditionally so a panicked
+        // tick doesn't leave the lock held for another replica.
+        let metadata = &self.metadata;
+        let pool = &self.pool;
+        let retention_days = self.retention_days;
+        let body = async move {
+            match metadata.run().await {
+                Ok(stats) => tracing::info!(?stats, "cron: metadata pass done"),
+                Err(e) => tracing::error!(?e, "cron: metadata pass failed"),
+            }
+            match pipeline::enqueue_bookmarked_pending(pool).await {
+                Ok(summary) => {
+                    tracing::info!(?summary, "cron: enqueued bookmarked-pending");
+                }
+                Err(e) => tracing::error!(?e, "cron: enqueue_bookmarked_pending failed"),
+            }
+            match jobs::reap_done(pool, retention_days).await {
+                Ok(n) => tracing::info!(reaped = n, "cron: done-job reaper finished"),
+                Err(e) => tracing::error!(?e, "cron: done-job reaper failed"),
+            }
+            if let Err(e) = write_last_tick(pool, Utc::now()).await {
+                tracing::warn!(?e, "cron: persist last_metadata_tick_at failed");
+            }
+        };
+        if let Err(_panic) = AssertUnwindSafe(body).catch_unwind().await {
+            tracing::error!("cron: tick body panicked — continuing");
         }
 
         let _ = sqlx::query("SELECT pg_advisory_unlock($1)")
@@ -317,14 +331,10 @@ impl WorkerContext {
         // (because a force-refetch race or a job that was re-enqueued
         // after a previous one finished), ack done without re-fetching.
         if let JobPayload::SyncChapterContent { chapter_id, .. } = &lease.payload {
-            let page_count: Option<i32> = sqlx::query_scalar(
-                "SELECT page_count FROM chapters WHERE id = $1",
-            )
-            .bind(chapter_id)
-            .fetch_optional(&self.pool)
-            .await
-            .ok()
-            .flatten();
+            let page_count = crate::repo::chapter::page_count(&self.pool, *chapter_id)
+                .await
+                .ok()
+                .flatten();
             if matches!(page_count, Some(n) if n > 0) {
                 let _ = jobs::ack_done(&self.pool, lease.id).await;
                 return;
@@ -630,4 +640,19 @@ mod tests {
         let prev = previous_fire(now, at, Tz::UTC);
         assert_eq!(prev, dt_utc(2026, 5, 24, 23, 30));
     }
+
+    /// Documents the panic-isolation pattern `run_tick` now relies on:
+    /// `AssertUnwindSafe(...).catch_unwind().await` must yield `Err(_)`
+    /// when the wrapped future panics, so the surrounding loop (or in
+    /// our case, the unconditional advisory-unlock that follows) keeps
+    /// running. The shape of this test mirrors the production callsite.
+    #[tokio::test]
+    async fn assert_unwind_safe_catches_a_panicking_future() {
+        let result = AssertUnwindSafe(async {
+            panic!("boom");
+        })
+        .catch_unwind()
+        .await;
+        assert!(result.is_err(), "panicking future must yield Err");
+    }
 }

backend/src/crawler/detect.rs

@@ -80,13 +80,36 @@ pub fn has_logo_sentinel(doc: &scraper::Html) -> bool {
 /// caller can fall back on the job system's retry/backoff once the
 /// inline budget is exhausted.
 pub async fn retry_on_transient<F, Fut, T>(
-    mut op: F,
+    op: F,
     max_attempts: u32,
     delay: Duration,
 ) -> Result<T, PageError>
 where
     F: FnMut() -> Fut,
     Fut: Future<Output = Result<T, PageError>>,
+{
+    retry_on_transient_with_hook(op, max_attempts, delay, || async {}).await
+}
+
+/// Like [`retry_on_transient`] but invokes `on_retry` between a
+/// transient failure and the subsequent sleep+retry. The hook does
+/// **not** fire on the first attempt, after a non-transient error, or
+/// after the final attempt (no retry follows). Hook failures are not
+/// propagated — return `()` from the future and log inside if needed.
+///
+/// Wire the TOR controller's `new_identity` here to rotate circuits
+/// between page-fetch retries; see [`crate::crawler::tor`].
+pub async fn retry_on_transient_with_hook<F, Fut, T, H, HFut>(
+    mut op: F,
+    max_attempts: u32,
+    delay: Duration,
+    mut on_retry: H,
+) -> Result<T, PageError>
+where
+    F: FnMut() -> Fut,
+    Fut: Future<Output = Result<T, PageError>>,
+    H: FnMut() -> HFut,
+    HFut: Future<Output = ()>,
 {
     debug_assert!(max_attempts >= 1, "max_attempts must be at least 1");
     let mut attempt = 0u32;
@@ -101,8 +124,9 @@ where
                     attempt,
                     max_attempts,
                     error = %e,
-                    "transient error; sleeping before retry"
+                    "transient error; running on-retry hook and sleeping before retry"
                 );
+                on_retry().await;
                 tokio::time::sleep(delay).await;
             }
         }
@@ -247,4 +271,92 @@ mod tests {
         assert_eq!(result.unwrap(), 7);
         assert_eq!(attempt, 1);
     }
+
+    #[tokio::test]
+    async fn hook_fires_once_between_transient_and_success() {
+        let mut attempt = 0u32;
+        let mut hook_calls = 0u32;
+        let result: Result<i32, PageError> = retry_on_transient_with_hook(
+            || {
+                attempt += 1;
+                let n = attempt;
+                async move {
+                    if n < 2 {
+                        Err(PageError::transient("once"))
+                    } else {
+                        Ok(99)
+                    }
+                }
+            },
+            5,
+            Duration::from_millis(0),
+            || {
+                hook_calls += 1;
+                async {}
+            },
+        )
+        .await;
+        assert_eq!(result.unwrap(), 99);
+        assert_eq!(attempt, 2);
+        assert_eq!(hook_calls, 1, "hook fires exactly once between attempts");
+    }
+
+    #[tokio::test]
+    async fn hook_does_not_fire_when_first_attempt_succeeds() {
+        let mut hook_calls = 0u32;
+        let result: Result<i32, PageError> = retry_on_transient_with_hook(
+            || async { Ok(1) },
+            5,
+            Duration::from_millis(0),
+            || {
+                hook_calls += 1;
+                async {}
+            },
+        )
+        .await;
+        assert!(result.is_ok());
+        assert_eq!(hook_calls, 0);
+    }
+
+    #[tokio::test]
+    async fn hook_does_not_fire_after_non_transient_error() {
+        let mut hook_calls = 0u32;
+        let result: Result<i32, PageError> = retry_on_transient_with_hook(
+            || async { Err(PageError::Other(anyhow::anyhow!("permanent"))) },
+            5,
+            Duration::from_millis(0),
+            || {
+                hook_calls += 1;
+                async {}
+            },
+        )
+        .await;
+        assert!(result.is_err());
+        assert_eq!(hook_calls, 0, "non-transient must short-circuit before hook");
+    }
+
+    #[tokio::test]
+    async fn hook_does_not_fire_after_final_failed_attempt() {
+        // With max_attempts=3 and three persistent transients, the hook
+        // should run twice (between 1→2 and 2→3) — never a third time,
+        // because no retry follows attempt 3.
+        let mut attempt = 0u32;
+        let mut hook_calls = 0u32;
+        let result: Result<i32, PageError> = retry_on_transient_with_hook(
+            || {
+                attempt += 1;
+                async { Err(PageError::transient("always")) }
+            },
+            3,
+            Duration::from_millis(0),
+            || {
+                hook_calls += 1;
+                async {}
+            },
+        )
+        .await;
+        assert!(result.is_err());
+        assert_eq!(attempt, 3);
+        assert_eq!(hook_calls, 2, "hook fires N-1 times for N attempts that all fail transient");
+    }
 }

backend/src/crawler/jobs.rs

@@ -1,4 +1,4 @@
-//! Persistent job queue and the four job kinds.
+//! Persistent job queue and its job kinds.
 //!
 //! Backed by Postgres (the `crawler_jobs` table). Workers lease rows
 //! with `SELECT ... FOR UPDATE SKIP LOCKED`, heartbeat via
@@ -12,16 +12,9 @@ use serde::{Deserialize, Serialize};
 use sqlx::PgPool;
 use uuid::Uuid;
 
-use super::source::DiscoverMode;
-
 #[derive(Clone, Debug, Serialize, Deserialize)]
 #[serde(tag = "kind", rename_all = "snake_case")]
 pub enum JobPayload {
-    /// Walk the source index and enqueue `SyncManga` jobs.
-    Discover {
-        source_id: String,
-        mode: DiscoverMode,
-    },
     /// Fetch one manga's detail page, upsert metadata, enqueue
     /// `SyncChapterList`.
     SyncManga {
@@ -111,6 +104,12 @@ pub async fn enqueue(pool: &PgPool, payload: &JobPayload) -> sqlx::Result<Enqueu
 ///
 /// `kind_filter` matches against `payload->>'kind'`; `None` means
 /// any kind.
+///
+/// Ties on `scheduled_at` (the common case: a cron batch enqueues
+/// everything with the same default `now()`) break by `created_at`, so
+/// jobs come off the queue in insertion order. The enqueue paths insert
+/// chapter-content jobs in ascending `chapters.number` order, so this
+/// tiebreaker is what propagates that intent through to dequeue.
 pub async fn lease(
     pool: &PgPool,
     kind_filter: Option<&str>,
@@ -125,7 +124,7 @@ pub async fn lease(
              WHERE (state = 'pending' OR (state = 'running' AND leased_until < now()))
                AND scheduled_at <= now()
                AND ($1::text IS NULL OR payload->>'kind' = $1)
-             ORDER BY scheduled_at
+             ORDER BY scheduled_at, created_at
              LIMIT $2
              FOR UPDATE SKIP LOCKED
         )
@@ -160,23 +159,36 @@ pub async fn lease(
     Ok(leases)
 }
 
-/// Mark a leased job as successfully completed.
+/// Mark a leased job as successfully completed. The `state = 'running'`
+/// predicate guards against a late ack from a worker whose lease expired
+/// and was already re-leased by another worker: without it, the late ack
+/// would clobber the new lease's `state` and `leased_until`. `rows_affected
+/// == 0` means we lost the lease — surfaced as a warn rather than an
+/// error because the new lease holder is doing real work; the late ack
+/// just has to step aside.
 pub async fn ack_done(pool: &PgPool, lease_id: Uuid) -> sqlx::Result<()> {
-    sqlx::query(
+    let res = sqlx::query(
         "UPDATE crawler_jobs \
             SET state = 'done', leased_until = NULL, updated_at = now() \
-          WHERE id = $1",
+          WHERE id = $1 AND state = 'running'",
     )
     .bind(lease_id)
     .execute(pool)
     .await?;
+    if res.rows_affected() == 0 {
+        tracing::warn!(
+            %lease_id,
+            "ack_done: lease no longer running — likely re-leased by another worker; skipping update"
+        );
+    }
     Ok(())
 }
 
 /// Mark a leased job as failed. If the current attempt count has reached
 /// `max_attempts` the job is terminally dead and stops retrying;
 /// otherwise it goes back to `pending` with `scheduled_at` pushed into
-/// the future by the exponential backoff.
+/// the future by the exponential backoff. See [`ack_done`] for the
+/// `state = 'running'` guard rationale.
 pub async fn ack_failed(
     pool: &PgPool,
     lease_id: Uuid,
@@ -184,16 +196,16 @@ pub async fn ack_failed(
     attempts: i32,
     max_attempts: i32,
 ) -> sqlx::Result<()> {
-    if attempts >= max_attempts {
+    let res = if attempts >= max_attempts {
         sqlx::query(
             "UPDATE crawler_jobs \
                 SET state = 'dead', last_error = $2, leased_until = NULL, updated_at = now() \
-              WHERE id = $1",
+              WHERE id = $1 AND state = 'running'",
         )
         .bind(lease_id)
         .bind(error)
         .execute(pool)
-        .await?;
+        .await?
     } else {
         let backoff_ms: i64 = backoff_for(attempts).as_millis().min(i64::MAX as u128) as i64;
         sqlx::query(
@@ -201,30 +213,45 @@ pub async fn ack_failed(
                 SET state = 'pending', last_error = $2, leased_until = NULL, \
                     scheduled_at = now() + ($3::bigint || ' milliseconds')::interval, \
                     updated_at = now() \
-              WHERE id = $1",
+              WHERE id = $1 AND state = 'running'",
         )
         .bind(lease_id)
         .bind(error)
         .bind(backoff_ms)
         .execute(pool)
-        .await?;
+        .await?
+    };
+    if res.rows_affected() == 0 {
+        tracing::warn!(
+            %lease_id,
+            "ack_failed: lease no longer running — likely re-leased by another worker; skipping update"
+        );
     }
     Ok(())
 }
 
 /// Return a leased job to `pending` without burning a retry attempt.
 /// Used on graceful shutdown and on session-expired aborts where the
-/// failure isn't the job's fault.
+/// failure isn't the job's fault. See [`ack_done`] for the
+/// `state = 'running'` guard rationale — important here because
+/// `attempts - 1` would otherwise spuriously decrement the new lease's
+/// attempt count.
 pub async fn release(pool: &PgPool, lease_id: Uuid) -> sqlx::Result<()> {
-    sqlx::query(
+    let res = sqlx::query(
         "UPDATE crawler_jobs \
             SET state = 'pending', leased_until = NULL, \
                 attempts = GREATEST(0, attempts - 1), updated_at = now() \
-          WHERE id = $1",
+          WHERE id = $1 AND state = 'running'",
     )
     .bind(lease_id)
     .execute(pool)
     .await?;
+    if res.rows_affected() == 0 {
+        tracing::warn!(
+            %lease_id,
+            "release: lease no longer running — likely re-leased by another worker; skipping update"
+        );
+    }
     Ok(())
 }
 

backend/src/crawler/mod.rs

@@ -20,7 +20,12 @@ pub mod daemon;
 pub mod detect;
 pub mod diff;
 pub mod jobs;
+pub mod nav;
 pub mod pipeline;
 pub mod rate_limit;
+pub mod resync;
+pub mod safety;
 pub mod session;
 pub mod source;
+pub mod tor;
+pub mod url_utils;

backend/src/crawler/nav.rs

@@ -0,0 +1,241 @@
+//! Page navigation helpers — wrap `chromiumoxide` `wait_for_navigation`
+//! with a timeout so a hung TLS handshake or a page that never fires
+//! `load` cannot wedge a worker (or the cron metadata pass) forever.
+//!
+//! [`NAV_TIMEOUT`] is the global budget. Callers in the crawler use
+//! [`wait_for_nav`] to get back a typed error so transient timeouts can
+//! be reported separately from underlying CDP errors.
+
+use std::time::Duration;
+
+use chromiumoxide::error::CdpError;
+use chromiumoxide::Page;
+use thiserror::Error;
+
+/// Maximum wall-clock time we'll wait for a single page navigation. A
+/// healthy Chromium reaches `load` in well under a second on the target
+/// site; a 30-second cap is generous enough for slow TLS handshakes on
+/// the first request after a fresh process while still catching real
+/// hangs before they wedge the daemon.
+pub const NAV_TIMEOUT: Duration = Duration::from_secs(30);
+
+/// Outcome of a timed-out navigation. `Timeout` is the transient signal
+/// callers translate into a retry-friendly error
+/// ([`crate::crawler::detect::PageError::Transient`] in the source path,
+/// a context'd anyhow elsewhere). `Cdp` carries the underlying
+/// chromiumoxide error unchanged.
+#[derive(Debug, Error)]
+pub enum NavError {
+    #[error("navigation timed out after {0:?}")]
+    Timeout(Duration),
+    #[error(transparent)]
+    Cdp(#[from] CdpError),
+}
+
+/// Wait for the page's next navigation to complete, capped at
+/// [`NAV_TIMEOUT`]. Replaces bare `page.wait_for_navigation().await`
+/// throughout the crawler.
+pub async fn wait_for_nav(page: &Page) -> Result<(), NavError> {
+    match tokio::time::timeout(NAV_TIMEOUT, page.wait_for_navigation()).await {
+        Err(_elapsed) => Err(NavError::Timeout(NAV_TIMEOUT)),
+        Ok(Err(e)) => Err(NavError::Cdp(e)),
+        Ok(Ok(_)) => Ok(()),
+    }
+}
+
+/// Poll interval for [`wait_for_selector`]. 100ms is fast enough that a
+/// page rendering in 200ms isn't held back noticeably, and slow enough
+/// not to spam CDP with `find_element` calls on a page that's actually
+/// taking its time.
+const SELECTOR_POLL_INTERVAL: Duration = Duration::from_millis(100);
+
+/// Wait until `selector` matches at least one element on `page`, or
+/// `timeout` elapses. Used after a navigation to confirm a page-type-
+/// specific marker is in the DOM before parsing — replaces the fixed
+/// post-nav sleep that previously masked partial-render races.
+///
+/// chromiumoxide 0.7.0 has no built-in `wait_for_selector`, so we poll
+/// `find_element` at [`SELECTOR_POLL_INTERVAL`] until success or budget
+/// exhaustion. A failed `find_element` is *not* an error here — it just
+/// means "not yet" — we only surface an error once the overall
+/// `timeout` is up.
+pub async fn wait_for_selector(
+    page: &Page,
+    selector: &str,
+    timeout: Duration,
+) -> Result<(), NavError> {
+    let deadline = tokio::time::Instant::now() + timeout;
+    loop {
+        if page.find_element(selector).await.is_ok() {
+            return Ok(());
+        }
+        if tokio::time::Instant::now() >= deadline {
+            return Err(NavError::Timeout(timeout));
+        }
+        let remaining = deadline.saturating_duration_since(tokio::time::Instant::now());
+        let sleep_for = SELECTOR_POLL_INTERVAL.min(remaining);
+        tokio::time::sleep(sleep_for).await;
+    }
+}
+
+/// Per-page-type budget for [`wait_for_selector`]. Shorter than
+/// [`NAV_TIMEOUT`] because by the time we're waiting on a selector, the
+/// page has already responded — we're only absorbing post-load JS
+/// finishing its row injection, which on a healthy site takes well
+/// under a second.
+pub const SELECTOR_TIMEOUT: Duration = Duration::from_secs(10);
+
+impl NavError {
+    /// Does this navigation error indicate the underlying Chromium
+    /// process has died or its CDP connection has dropped? Used by the
+    /// dispatcher to decide whether to invalidate the
+    /// [`crate::crawler::browser_manager::BrowserManager`] handle so
+    /// the next acquire re-launches.
+    ///
+    /// Both variants count: a `Timeout` past [`NAV_TIMEOUT`] is in
+    /// practice always either a hung CDP transport or a wedged page
+    /// the browser can't recover from on its own, and a `Cdp` error
+    /// surfacing at the navigation layer means the chromium-facing
+    /// channel is the failing layer.
+    pub fn is_likely_browser_dead(&self) -> bool {
+        match self {
+            Self::Timeout(_) => true,
+            Self::Cdp(_) => true,
+        }
+    }
+}
+
+/// Walk an `anyhow::Error` chain looking for typed evidence that the
+/// chromium-facing layer is the failing one. Two markers count:
+///
+/// 1. A wrapped [`NavError`] flagged by [`NavError::is_likely_browser_dead`].
+/// 2. A wrapped [`CdpError`] (via `anyhow::Error::from(CdpError)` at a
+///    `Browser::new_page` call site, or any other direct CDP boundary).
+///
+/// Earlier versions also substring-matched the chain for "connection",
+/// "closed", "channel", etc. as a fallback. That was too broad —
+/// reqwest TCP-reset errors during CDN image downloads, sqlx
+/// connection-pool errors, and similar non-browser failures contain
+/// those words and triggered spurious chromium relaunches. The typed
+/// downcasts cover every place we hand a chromium error to anyhow,
+/// so the fallback is unnecessary.
+pub fn anyhow_looks_browser_dead(err: &anyhow::Error) -> bool {
+    for cause in err.chain() {
+        if let Some(nav) = cause.downcast_ref::<NavError>() {
+            if nav.is_likely_browser_dead() {
+                return true;
+            }
+        }
+        if cause.downcast_ref::<CdpError>().is_some() {
+            return true;
+        }
+    }
+    false
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::future::pending;
+
+    /// Sanity-check the timeout pattern used by [`wait_for_nav`]: a
+    /// future that never resolves must yield `Elapsed` within the
+    /// configured budget. We can't easily stand up a real `Page` in a
+    /// unit test, so we assert the underlying primitive behaves the way
+    /// the helper depends on.
+    #[tokio::test(flavor = "current_thread", start_paused = true)]
+    async fn timeout_elapses_on_a_future_that_never_resolves() {
+        let result =
+            tokio::time::timeout(Duration::from_millis(50), pending::<()>()).await;
+        assert!(result.is_err(), "expected Elapsed on a hung future");
+    }
+
+    #[test]
+    fn nav_error_timeout_message_includes_duration() {
+        let e = NavError::Timeout(Duration::from_secs(30));
+        assert_eq!(e.to_string(), "navigation timed out after 30s");
+    }
+
+    #[test]
+    fn timeout_is_treated_as_likely_browser_dead() {
+        let e = NavError::Timeout(NAV_TIMEOUT);
+        assert!(e.is_likely_browser_dead());
+    }
+
+    #[test]
+    fn anyhow_with_nav_timeout_in_chain_is_flagged() {
+        let inner: Result<(), NavError> = Err(NavError::Timeout(NAV_TIMEOUT));
+        let outer = inner.unwrap_err();
+        let wrapped: anyhow::Error =
+            anyhow::Error::new(outer).context("wait for chapter nav");
+        assert!(anyhow_looks_browser_dead(&wrapped));
+    }
+
+    #[test]
+    fn anyhow_with_cdp_error_in_chain_is_flagged() {
+        // `Browser::new_page` errors get wrapped via
+        // `anyhow::Error::from(CdpError)` at the navigate / dispatch
+        // call sites. Walking the chain and downcasting to CdpError is
+        // what catches that path. Any CdpError variant counts; the
+        // Serde variant is the easiest to construct in a unit test.
+        let serde_err: serde_json::Error =
+            serde_json::from_str::<i32>("not a number").unwrap_err();
+        let cdp = CdpError::Serde(serde_err);
+        let wrapped: anyhow::Error =
+            anyhow::Error::from(cdp).context("open chapter page");
+        assert!(anyhow_looks_browser_dead(&wrapped));
+    }
+
+    #[test]
+    fn anyhow_with_innocuous_parse_error_is_not_flagged() {
+        let e: anyhow::Error =
+            anyhow::anyhow!("parse manga detail: chapter row regex did not match");
+        assert!(!anyhow_looks_browser_dead(&e));
+    }
+
+    #[test]
+    fn anyhow_with_reqwest_style_connection_message_is_not_flagged() {
+        // Regression: the earlier substring fallback flagged any error
+        // whose message contained "connection" or "closed" as browser-
+        // dead. A TCP reset from a CDN during image download, or a
+        // sqlx pool-connection error, would burn a chromium relaunch
+        // even though the browser is fine. Typed downcasts only —
+        // these untyped strings must pass through.
+        for msg in [
+            "error sending request: connection reset by peer",
+            "PoolTimedOut: timed out waiting for a connection",
+            "request to https://cdn/x.jpg: connection closed before message completed",
+            "transport error during image fetch",
+        ] {
+            let e: anyhow::Error = anyhow::anyhow!("{msg}");
+            assert!(
+                !anyhow_looks_browser_dead(&e),
+                "must not flag non-browser error: {msg}"
+            );
+        }
+    }
+
+    /// Same sanity check as [`timeout_elapses_on_a_future_that_never_resolves`],
+    /// but for the [`wait_for_selector`] polling pattern: the loop must
+    /// surrender on `Elapsed` rather than spinning past the deadline.
+    #[tokio::test(flavor = "current_thread", start_paused = true)]
+    async fn selector_polling_pattern_surrenders_at_deadline() {
+        let timeout = Duration::from_millis(300);
+        let start = tokio::time::Instant::now();
+        let deadline = start + timeout;
+        // Simulate find_element forever returning "not found".
+        let mut polls = 0u32;
+        let result: Result<(), NavError> = loop {
+            polls += 1;
+            if tokio::time::Instant::now() >= deadline {
+                break Err(NavError::Timeout(timeout));
+            }
+            tokio::time::sleep(SELECTOR_POLL_INTERVAL).await;
+        };
+        assert!(matches!(result, Err(NavError::Timeout(_))));
+        // 300ms / 100ms poll interval ≈ 3 iterations plus the final check
+        // that breaks out. Allow some slack since the first poll happens
+        // before any sleep.
+        assert!(polls >= 3, "expected at least 3 poll iterations, got {polls}");
+    }
+}

backend/src/crawler/pipeline.rs

@@ -2,6 +2,8 @@
 //! that fan out chapter-content work. Shared between the daemon (cron tick)
 //! and the CLI (`bin/crawler.rs`) so behavior stays in lockstep.
 
+use std::collections::HashSet;
+
 use anyhow::Context;
 use sqlx::PgPool;
 use uuid::Uuid;
@@ -9,9 +11,11 @@ use uuid::Uuid;
 use crate::crawler::browser_manager::BrowserManager;
 use crate::crawler::jobs::{self, EnqueueResult, JobPayload};
 use crate::crawler::rate_limit::HostRateLimiters;
+use crate::crawler::safety::{fetch_bytes_capped, looks_like_image, DownloadAllowlist};
 use crate::crawler::source::target::TargetSource;
-use crate::crawler::source::{DiscoverMode, FetchContext, Source};
+use crate::crawler::source::{FetchContext, Source, SourceMangaRef};
 use crate::repo;
+use crate::repo::crawler::UpsertStatus;
 use crate::storage::Storage;
 
 /// Coarse counters surfaced for logging at the end of a metadata pass.
@@ -23,16 +27,42 @@ pub struct MetadataStats {
     pub mangas_failed: usize,
 }
 
-/// Decide whether the per-ref loop should stop based on the Incremental
-/// streak counter. Pulled out as a pure function so the rule is unit-
-/// testable without standing up the walker or DB.
-pub(crate) fn should_stop(mode: DiscoverMode, consecutive_unchanged: usize) -> bool {
-    match mode {
-        DiscoverMode::Backfill => false,
-        DiscoverMode::Incremental { stop_after_unchanged } => {
-            consecutive_unchanged >= stop_after_unchanged
-        }
-    }
+/// Decide whether the per-ref loop should stop on the manga just
+/// processed. The walk halts only when (a) the previous run exited
+/// cleanly — so the index tail is known to be caught up and we're not
+/// in a recovery sweep — AND (b) this manga's metadata hash matched
+/// storage (`Unchanged`) AND (c) the chapter sync confirmed zero new
+/// chapters. A `None` chapter count (skip_chapters, or a chapter-sync
+/// error we logged-and-swallowed) refuses the stop because we can't
+/// verify the tail is unchanged from a single piece of evidence.
+///
+/// Pure function so the rule is unit-testable without the walker, DB,
+/// or browser.
+pub(crate) fn should_stop(
+    was_clean: bool,
+    status: UpsertStatus,
+    chapters_new: Option<usize>,
+) -> bool {
+    was_clean
+        && matches!(status, UpsertStatus::Unchanged)
+        && chapters_new == Some(0)
+}
+
+/// Whether the just-finished walk should be recorded as a clean exit.
+/// `true` writes the recovery flag back to `completed: true`; `false`
+/// leaves it `false` so the next tick treats this run as crashed and
+/// does a recovery sweep.
+///
+/// `hit_limit` (the caller-imposed `CRAWLER_LIMIT` cap) is *not* an
+/// argument: a limit cap by definition does not reach the catalog tail,
+/// so it can never count as a clean exit. Encoding that in the type
+/// (rather than as an `&& !hit_limit` clause inline) prevents a future
+/// edit from accidentally adding it back to the truth table.
+pub(crate) fn should_mark_clean_exit(
+    walked_to_completion: bool,
+    hit_stop_condition: bool,
+) -> bool {
+    walked_to_completion || hit_stop_condition
 }
 
 /// Runs the discover → fetch → upsert → cover → chapter-list-diff pipeline
@@ -42,15 +72,25 @@ pub(crate) fn should_stop(mode: DiscoverMode, consecutive_unchanged: usize) -> b
 /// `limit == 0` means no cap (full sweep up to the source's own bound).
 /// `skip_chapters == true` is the "metadata-only" mode (parser doesn't
 /// extract chapters, and `sync_manga_chapters` is skipped — otherwise an
-/// empty chapter list would soft-drop existing rows).
+/// empty chapter list would soft-drop existing rows). In this mode the
+/// stop condition never fires because chapter freshness can't be
+/// confirmed, so the walk always runs to end-of-source.
 ///
-/// `mode` controls the walk:
-/// - `Backfill` — oldest-first, no early exit. The only mode that runs
-///   the end-of-walk drop pass + writes `seed_completed_at`.
-/// - `Incremental { stop_after_unchanged }` — newest-first, breaks out
-///   after N consecutive Unchanged upserts. Drop pass is skipped (the
-///   tail of the index is never visited, so its `last_seen_at` is
-///   stale and using it to soft-drop would be unsafe).
+/// The walk is always newest-first. Steady-state runs stop on the first
+/// manga where metadata is `Unchanged` AND chapter sync reports zero
+/// new chapters — the source orders by `update_date DESC`, so anything
+/// with a fresh chapter or fresh metadata is bumped to the top and will
+/// be processed before we hit a fully-caught-up manga.
+///
+/// A per-source recovery flag stored in `crawler_state`
+/// (`last_run_completed:<source_id>`) gates the early stop: it's set to
+/// `false` right after `ensure_source` and back to `true` only when the
+/// run exits via end-of-walk OR the intentional stop. A crash, panic,
+/// or SIGKILL leaves the flag at `false`, so the next tick reads it,
+/// recognizes the previous run did not exit cleanly, and walks the
+/// full catalog (ignoring the stop condition) to re-cover anything the
+/// crashed run missed past its crash point. Once that recovery sweep
+/// reaches end-of-walk, steady-state resumes.
 #[allow(clippy::too_many_arguments)]
 pub async fn run_metadata_pass(
     browser_manager: &BrowserManager,
@@ -61,7 +101,9 @@ pub async fn run_metadata_pass(
     start_url: &str,
     limit: usize,
     skip_chapters: bool,
-    mode: DiscoverMode,
+    allowlist: &DownloadAllowlist,
+    max_image_bytes: usize,
+    tor: Option<&crate::crawler::tor::TorController>,
 ) -> anyhow::Result<MetadataStats> {
     let lease = browser_manager
         .acquire()
@@ -80,6 +122,7 @@ pub async fn run_metadata_pass(
     let ctx = FetchContext {
         browser: browser_ref,
         rate,
+        tor,
     };
 
     let source_id = source.id();
@@ -92,20 +135,36 @@ pub async fn run_metadata_pass(
     .await
     .context("ensure_source")?;
 
-    let run_started_at = chrono::Utc::now();
+    // Read BEFORE flipping to "in-flight" — a `false` here means the
+    // previous run didn't reach a clean exit, and this run must walk
+    // the full catalog (recovery sweep) instead of bailing on the
+    // first caught-up manga.
+    let was_clean = repo::crawler::last_run_completed_cleanly(db, source_id)
+        .await
+        .context("read last_run_completed_cleanly")?;
+    repo::crawler::mark_run_started(db, source_id)
+        .await
+        .context("mark_run_started")?;
+
     let max_refs = (limit > 0).then_some(limit);
 
-    tracing::info!(?mode, ?max_refs, "starting metadata pass");
+    tracing::info!(was_clean, ?max_refs, "starting metadata pass");
     let mut walker = source
-        .discover(&ctx, mode)
+        .discover(&ctx)
         .await
         .context("discover failed")?;
 
     let mut stats = MetadataStats::default();
-    let mut consecutive_unchanged: usize = 0;
+    // Run-scoped dedup of `source_manga_key`s already processed this pass.
+    // A shift in the source index causes the slot-last item of the page
+    // we just read to reappear at slot 0 of the next page; skipping it
+    // here prevents redundant fetch_manga + upsert and avoids spuriously
+    // tripping the stop condition with a re-confirm of an entry we
+    // already counted.
+    let mut seen: HashSet<String> = HashSet::new();
     let mut walked_to_completion = false;
     let mut hit_limit = false;
-    let mut hit_incremental_stop = false;
+    let mut hit_stop_condition = false;
 
     'outer: loop {
         let batch = match walker.next_batch(&ctx).await? {
@@ -121,6 +180,23 @@ pub async fn run_metadata_pass(
                 tracing::info!(cap = ?max_refs, "max_results reached; halting walk");
                 break 'outer;
             }
+            // Skip refs we've already *successfully* processed this pass.
+            // Checking `contains` here (rather than `insert`) keeps the key
+            // out of `seen` on failure paths below, so a transient fetch or
+            // upsert error gets a second chance if the ref reappears in
+            // another batch. Done *before* counting toward
+            // `stats.discovered` (the skipped ref did no work) and *before*
+            // touching the stop check (a `continue` here doesn't let a
+            // re-confirm trip the stop condition). The matching
+            // `seen.insert(...)` lives just after the successful upsert
+            // below.
+            if seen.contains(&r.source_manga_key) {
+                tracing::debug!(
+                    key = %r.source_manga_key,
+                    "skip already-seen key in this run"
+                );
+                continue;
+            }
             stats.discovered += 1;
             tracing::info!(
                 idx = stats.discovered,
@@ -141,6 +217,48 @@ pub async fn run_metadata_pass(
                 }
             };
 
+            // Partial-render guard: an empty chapter list paired with a
+            // prior count > 0 is overwhelmingly a chromium snapshot
+            // taken between the #chapter_table wrapper render and its
+            // rows render. The wait_for_selector wait in `navigate`
+            // narrows this window but cannot close it for slow renders
+            // beyond the selector budget. Treat as a transient failure
+            // here — skip upsert, skip seen.insert — so the next batch
+            // (or the next tick) retries. Skipped in `skip_chapters`
+            // mode because the parser is configured to return an empty
+            // Vec by design there.
+            if !skip_chapters && manga.chapters.is_empty() {
+                match repo::crawler::live_chapter_count_for_source_manga(
+                    db, source_id, &r.source_manga_key,
+                )
+                .await
+                {
+                    Ok(prior) if prior > 0 => {
+                        tracing::warn!(
+                            key = %r.source_manga_key,
+                            url = %r.url,
+                            prior_chapter_count = prior,
+                            "fetch_manga returned empty chapters but prior count > 0; treating as partial-render transient and skipping"
+                        );
+                        stats.mangas_failed += 1;
+                        continue;
+                    }
+                    Ok(_) => {}
+                    Err(e) => {
+                        // DB lookup failed — fail safe: skip rather
+                        // than risk a soft-drop on a manga whose prior
+                        // count we couldn't confirm.
+                        tracing::warn!(
+                            key = %r.source_manga_key,
+                            error = ?e,
+                            "live_chapter_count_for_source_manga failed; skipping cautiously"
+                        );
+                        stats.mangas_failed += 1;
+                        continue;
+                    }
+                }
+            }
+
             let upsert = match repo::crawler::upsert_manga_from_source(
                 db, source_id, &r.url, &manga,
             )
@@ -158,6 +276,10 @@ pub async fn run_metadata_pass(
                 }
             };
             stats.upserted += 1;
+            // Record success in the dedup set. Cover and chapter-sync
+            // failures below are non-fatal and don't roll this back —
+            // metadata is the durable source of truth for the dedup.
+            seen.insert(r.source_manga_key.clone());
             tracing::info!(
                 key = %manga.source_manga_key,
                 manga_id = %upsert.manga_id,
@@ -181,6 +303,8 @@ pub async fn run_metadata_pass(
                         &r.url,
                         upsert.manga_id,
                         cover_url,
+                        allowlist,
+                        max_image_bytes,
                     )
                     .await
                     {
@@ -194,7 +318,13 @@ pub async fn run_metadata_pass(
                 }
             }
 
-            if !skip_chapters {
+            // Chapter sync. `chapters_new` feeds the stop check below:
+            // `None` (skip_chapters mode, or a logged-and-swallowed sync
+            // error) refuses to stop on this manga because we can't
+            // confirm "no new chapters."
+            let chapters_new: Option<usize> = if skip_chapters {
+                None
+            } else {
                 match repo::crawler::sync_manga_chapters(
                     db,
                     source_id,
@@ -203,79 +333,64 @@ pub async fn run_metadata_pass(
                 )
                 .await
                 {
-                    Ok(diff) => tracing::info!(
-                        manga_id = %upsert.manga_id,
-                        new = diff.new,
-                        refreshed = diff.refreshed,
-                        dropped = diff.dropped,
-                        "chapters synced"
-                    ),
-                    Err(e) => tracing::warn!(
-                        manga_id = %upsert.manga_id,
-                        error = ?e,
-                        "chapter sync failed"
-                    ),
+                    Ok(diff) => {
+                        tracing::info!(
+                            manga_id = %upsert.manga_id,
+                            new = diff.new,
+                            refreshed = diff.refreshed,
+                            dropped = diff.dropped,
+                            "chapters synced"
+                        );
+                        Some(diff.new)
+                    }
+                    Err(e) => {
+                        tracing::warn!(
+                            manga_id = %upsert.manga_id,
+                            error = ?e,
+                            "chapter sync failed"
+                        );
+                        None
+                    }
                 }
-            }
+            };
 
-            // Incremental stop: count consecutive Unchanged upserts and
-            // bail once the threshold is reached. New/Updated resets the
-            // streak so a fresh entry mid-batch doesn't accidentally trip
-            // the cutoff.
-            match upsert.status {
-                repo::crawler::UpsertStatus::Unchanged => {
-                    consecutive_unchanged += 1;
-                }
-                repo::crawler::UpsertStatus::New | repo::crawler::UpsertStatus::Updated => {
-                    consecutive_unchanged = 0;
-                }
-            }
-            if should_stop(mode, consecutive_unchanged) {
-                hit_incremental_stop = true;
+            if should_stop(was_clean, upsert.status, chapters_new) {
+                hit_stop_condition = true;
                 tracing::info!(
-                    consecutive_unchanged,
-                    "incremental stop threshold reached; halting walk"
+                    key = %manga.source_manga_key,
+                    "stop condition met (Unchanged metadata + 0 new chapters); halting walk"
                 );
                 break 'outer;
             }
         }
     }
 
-    // Drop pass: only when the walk truly covered everything the source
-    // surfaces. `last_seen_at` on un-visited rows is stale, so running
-    // the drop on a partial walk would soft-drop the tail of the index.
-    let full_walk = walked_to_completion && !hit_limit && !hit_incremental_stop;
-    let backfill_complete = full_walk && matches!(mode, DiscoverMode::Backfill);
-    if full_walk {
-        match repo::crawler::mark_dropped_mangas(db, source_id, run_started_at).await {
-            Ok(n) => tracing::info!(dropped = n, "marked unseen manga as dropped"),
-            Err(e) => tracing::warn!(error = ?e, "drop-pass failed"),
-        }
-    } else {
-        tracing::info!(
-            ?mode,
-            hit_limit,
-            hit_incremental_stop,
-            "partial sync — skipping drop pass"
-        );
-    }
-    if backfill_complete {
-        if let Err(e) = repo::crawler::mark_seed_completed(db, source_id, run_started_at).await {
-            tracing::warn!(error = ?e, "mark_seed_completed failed");
-        } else {
-            tracing::info!(source_id, "seed marked complete");
+    // Recovery-flag write. Only on a clean exit (end-of-walk OR the
+    // intentional stop). `hit_limit` is a caller-imposed early break
+    // and does NOT count — the catalog tail wasn't reached, so a future
+    // tick still needs to walk past where we stopped. The truth table is
+    // pinned by `should_mark_clean_exit` so a future edit that adds
+    // `hit_limit` back into the disjunction trips its unit test. Flag-
+    // write errors are warned and swallowed: the run already did its
+    // work, and a stale `false` flag just buys a recovery sweep on the
+    // next tick.
+    let exited_cleanly = should_mark_clean_exit(walked_to_completion, hit_stop_condition);
+    if exited_cleanly {
+        if let Err(e) = repo::crawler::mark_run_completed(db, source_id).await {
+            tracing::warn!(error = ?e, "mark_run_completed failed");
         }
     }
 
     tracing::info!(
-        ?mode,
+        was_clean,
         discovered = stats.discovered,
         upserted = stats.upserted,
         covers_fetched = stats.covers_fetched,
         mangas_failed = stats.mangas_failed,
         walked_to_completion,
         hit_limit,
-        hit_incremental_stop,
+        hit_stop_condition,
+        exited_cleanly,
         "metadata pass complete"
     );
 
@@ -283,8 +398,20 @@ pub async fn run_metadata_pass(
     Ok(stats)
 }
 
+/// Quarantine window for chapters whose latest `SyncChapterContent` job is
+/// `dead`. The partial dedup index `crawler_jobs_chapter_content_dedup_idx`
+/// only blocks `(pending|running)` duplicates, so without this gate a
+/// permanently-failing chapter is re-enqueued every cron tick, burns
+/// `max_attempts` retries, dies again, and spins forever. With the gate,
+/// dead chapters get a week of silence before the next attempt — long
+/// enough for a transient site issue to resolve, short enough that
+/// permanent failures don't stay permanent if conditions change.
+const CHAPTER_DEAD_QUARANTINE_DAYS: i64 = 7;
+
 /// Enqueue a `SyncChapterContent` job for every chapter of *any* bookmarked
 /// manga that still has `page_count = 0` and a non-dropped source row.
+/// Chapters whose latest job is `dead` within `CHAPTER_DEAD_QUARANTINE_DAYS`
+/// are excluded to break the dead-letter spin.
 /// Returns `(inserted, skipped)` counts. Dedup index handles repeats.
 pub async fn enqueue_bookmarked_pending(pool: &PgPool) -> anyhow::Result<EnqueueSummary> {
     let rows: Vec<(String, Uuid, String)> = sqlx::query_as(
@@ -295,10 +422,18 @@ pub async fn enqueue_bookmarked_pending(pool: &PgPool) -> anyhow::Result<Enqueue
           JOIN chapter_sources cs ON cs.chapter_id = c.id
          WHERE c.page_count = 0
            AND cs.dropped_at IS NULL
-         GROUP BY cs.source_id, c.id, cs.source_chapter_key, c.manga_id, c.created_at
-         ORDER BY c.manga_id, c.created_at ASC
+           AND NOT EXISTS (
+               SELECT 1 FROM crawler_jobs cj
+                WHERE cj.payload->>'kind' = 'sync_chapter_content'
+                  AND cj.payload->>'chapter_id' = c.id::text
+                  AND cj.state = 'dead'
+                  AND cj.updated_at > now() - ($1::bigint || ' days')::interval
+           )
+         GROUP BY cs.source_id, c.id, cs.source_chapter_key, c.manga_id, c.number, c.created_at
+         ORDER BY c.manga_id, c.number ASC, c.created_at ASC
         "#,
     )
+    .bind(CHAPTER_DEAD_QUARANTINE_DAYS)
     .fetch_all(pool)
     .await
     .context("query bookmarked-pending chapters")?;
@@ -327,23 +462,34 @@ pub async fn enqueue_bookmarked_pending(pool: &PgPool) -> anyhow::Result<Enqueue
 }
 
 /// Enqueue chapter-content jobs for a *single* manga (the bookmark-create
-/// hook). Same dedup semantics as [`enqueue_bookmarked_pending`].
+/// hook). Same dedup semantics as [`enqueue_bookmarked_pending`], including
+/// the dead-letter quarantine — a freshly bookmarked manga should not
+/// burn retries on chapters that just died on the cron tick.
 pub async fn enqueue_pending_for_manga(
     pool: &PgPool,
     manga_id: Uuid,
 ) -> anyhow::Result<EnqueueSummary> {
     let rows: Vec<(String, Uuid, String)> = sqlx::query_as(
         r#"
-        SELECT DISTINCT cs.source_id, c.id AS chapter_id, cs.source_chapter_key
+        SELECT cs.source_id, c.id AS chapter_id, cs.source_chapter_key
           FROM chapters c
           JOIN chapter_sources cs ON cs.chapter_id = c.id
          WHERE c.manga_id = $1
            AND c.page_count = 0
            AND cs.dropped_at IS NULL
-         ORDER BY cs.source_id, c.id
+           AND NOT EXISTS (
+               SELECT 1 FROM crawler_jobs cj
+                WHERE cj.payload->>'kind' = 'sync_chapter_content'
+                  AND cj.payload->>'chapter_id' = c.id::text
+                  AND cj.state = 'dead'
+                  AND cj.updated_at > now() - ($2::bigint || ' days')::interval
+           )
+         GROUP BY cs.source_id, c.id, cs.source_chapter_key, c.number, c.created_at
+         ORDER BY c.number ASC, c.created_at ASC, cs.source_id
         "#,
     )
     .bind(manga_id)
+    .bind(CHAPTER_DEAD_QUARANTINE_DAYS)
     .fetch_all(pool)
     .await
     .context("query pending chapters for manga")?;
@@ -378,11 +524,133 @@ pub struct EnqueueSummary {
     pub failed: usize,
 }
 
+#[derive(Debug, Default, Clone, Copy)]
+pub struct CoverBackfillStats {
+    pub considered: usize,
+    pub fetched: usize,
+    pub failed: usize,
+}
+
+/// Default per-tick cap for [`backfill_missing_covers`]. The metadata pass
+/// already retries covers when its walk reaches the affected manga; this
+/// backfill exists to catch the residual case where the early-stop
+/// optimisation prevents the walk from reaching mangas whose cover failed
+/// on first attempt. A small cap is enough because the backlog only grows
+/// from sporadic download failures, not from systematic misses.
+pub const COVER_BACKFILL_DEFAULT_MAX: usize = 10;
+
+/// Re-attempt cover downloads for mangas where `cover_image_path IS NULL`
+/// but a live `manga_sources` row exists. Refetches the source detail
+/// page (which is where the cover URL lives) and downloads the cover.
+///
+/// Bounded by `max_mangas` per call so a steady stream of failing covers
+/// — e.g. a CDN host that's persistently 502 — can't monopolise a cron
+/// tick. Orders by `manga_sources.last_seen_at DESC` so the freshest
+/// missing-cover mangas are addressed first.
+///
+/// Failures are logged and counted, not raised: a single bad cover URL
+/// must not stall every other backfill behind it.
+#[allow(clippy::too_many_arguments)]
+pub async fn backfill_missing_covers(
+    browser_manager: &BrowserManager,
+    db: &PgPool,
+    storage: &dyn Storage,
+    http: &reqwest::Client,
+    rate: &HostRateLimiters,
+    max_mangas: usize,
+    allowlist: &DownloadAllowlist,
+    max_image_bytes: usize,
+    tor: Option<&crate::crawler::tor::TorController>,
+) -> anyhow::Result<CoverBackfillStats> {
+    let mut stats = CoverBackfillStats::default();
+    if max_mangas == 0 {
+        return Ok(stats);
+    }
+
+    let entries = repo::crawler::list_missing_covers(db, max_mangas as i64)
+        .await
+        .context("list_missing_covers")?;
+
+    if entries.is_empty() {
+        return Ok(stats);
+    }
+
+    let lease = browser_manager
+        .acquire()
+        .await
+        .context("acquire browser lease for cover backfill")?;
+    let browser_ref: &chromiumoxide::Browser = &lease;
+    let ctx = FetchContext { browser: browser_ref, rate, tor };
+
+    for entry in entries {
+        stats.considered += 1;
+        // Metadata-only TargetSource: skip chapter-list parsing so a
+        // missing-cover refetch doesn't soft-drop chapters on a partial
+        // render. Cover URL alone is what we need.
+        let source = TargetSource::new(entry.source_url.clone()).without_chapter_parsing();
+        let r = SourceMangaRef {
+            source_manga_key: entry.source_manga_key.clone(),
+            title: String::new(),
+            url: entry.source_url.clone(),
+        };
+        let cover_url = match source.fetch_manga(&ctx, &r).await {
+            Ok(manga) => manga.cover_url,
+            Err(e) => {
+                tracing::warn!(
+                    manga_id = %entry.manga_id,
+                    url = %entry.source_url,
+                    error = ?e,
+                    "cover backfill: fetch_manga failed"
+                );
+                stats.failed += 1;
+                continue;
+            }
+        };
+        let Some(cover_url) = cover_url else {
+            tracing::warn!(
+                manga_id = %entry.manga_id,
+                url = %entry.source_url,
+                "cover backfill: source returned no cover_url"
+            );
+            stats.failed += 1;
+            continue;
+        };
+        match download_and_store_cover(
+            db,
+            storage,
+            http,
+            rate,
+            &entry.source_url,
+            entry.manga_id,
+            &cover_url,
+            allowlist,
+            max_image_bytes,
+        )
+        .await
+        {
+            Ok(()) => stats.fetched += 1,
+            Err(e) => {
+                tracing::warn!(
+                    manga_id = %entry.manga_id,
+                    url = %entry.source_url,
+                    error = ?e,
+                    "cover backfill: download failed"
+                );
+                stats.failed += 1;
+            }
+        }
+    }
+
+    drop(lease);
+    Ok(stats)
+}
+
 /// Download a cover image and persist its storage path. Local to the
 /// pipeline because the CLI still calls it from its inline chapter-content
 /// loop; once the worker pool fully replaces that path we can fold this
 /// into `pipeline` proper.
-async fn download_and_store_cover(
+#[allow(clippy::too_many_arguments)]
+pub(crate) async fn download_and_store_cover(
     db: &PgPool,
     storage: &dyn Storage,
     http: &reqwest::Client,
@@ -390,6 +658,8 @@ async fn download_and_store_cover(
     manga_url: &str,
     manga_id: Uuid,
     cover_url: &str,
+    allowlist: &DownloadAllowlist,
+    max_image_bytes: usize,
 ) -> anyhow::Result<()> {
     let absolute = reqwest::Url::parse(manga_url)
         .context("parse manga URL")?
@@ -397,17 +667,22 @@ async fn download_and_store_cover(
         .context("join cover URL onto manga URL")?;
 
     rate.wait_for(absolute.as_str()).await?;
-    let resp = http
-        .get(absolute.clone())
-        .header(reqwest::header::REFERER, manga_url)
-        .send()
-        .await
-        .with_context(|| format!("GET {absolute}"))?
-        .error_for_status()
-        .with_context(|| format!("non-2xx for {absolute}"))?;
-    let bytes = resp.bytes().await.context("read cover body")?;
-    let kind = infer::get(&bytes);
-    let ext = kind.map(|k| k.extension()).unwrap_or("bin");
+    let bytes = fetch_bytes_capped(
+        http,
+        absolute.as_str(),
+        Some(manga_url),
+        allowlist,
+        max_image_bytes,
+    )
+    .await?;
+    if !looks_like_image(&bytes) {
+        anyhow::bail!(
+            "cover URL {absolute} returned non-image bytes; refusing to store as binary blob"
+        );
+    }
+    let ext = infer::get(&bytes)
+        .map(|k| k.extension())
+        .expect("looks_like_image asserted infer succeeded");
     let key = format!("mangas/{manga_id}/cover.{ext}");
 
     storage
@@ -427,41 +702,112 @@ async fn download_and_store_cover(
     Ok(())
 }
 
-fn origin_of(url: &str) -> Option<String> {
-    let (scheme, rest) = url.split_once("://")?;
-    let host = rest.split('/').next()?;
-    Some(format!("{scheme}://{host}"))
-}
+use crate::crawler::url_utils::origin_of;
 
 #[cfg(test)]
 mod tests {
     use super::*;
 
     #[test]
-    fn backfill_never_stops_regardless_of_streak() {
-        assert!(!should_stop(DiscoverMode::Backfill, 0));
-        assert!(!should_stop(DiscoverMode::Backfill, 100));
-        assert!(!should_stop(DiscoverMode::Backfill, usize::MAX));
+    fn stop_condition_fires_on_unchanged_metadata_and_zero_new_chapters() {
+        // The whole point of the rule: in steady state, a manga whose
+        // metadata hash matches AND whose chapter list gained no new
+        // entries proves we've reached the caught-up tail of a
+        // newest-first index.
+        assert!(should_stop(true, UpsertStatus::Unchanged, Some(0)));
     }
 
     #[test]
-    fn incremental_stops_when_streak_meets_threshold() {
-        let mode = DiscoverMode::Incremental {
-            stop_after_unchanged: 3,
-        };
-        assert!(!should_stop(mode, 0));
-        assert!(!should_stop(mode, 2));
-        assert!(should_stop(mode, 3), "stops at exactly the threshold");
-        assert!(should_stop(mode, 100), "stops at anything past threshold");
+    fn stop_condition_refuses_when_chapters_added() {
+        // Unchanged metadata + N new chapters means the source bumped
+        // this manga because of the chapter add; the rest of the index
+        // is still ahead of us. Don't bail.
+        assert!(!should_stop(true, UpsertStatus::Unchanged, Some(1)));
+        assert!(!should_stop(true, UpsertStatus::Unchanged, Some(42)));
     }
 
     #[test]
-    fn incremental_with_zero_threshold_stops_immediately() {
-        // A nonsensical config (no Unchanged needed to stop) shouldn't
-        // panic — it just means the very first ref triggers the bail.
-        let mode = DiscoverMode::Incremental {
-            stop_after_unchanged: 0,
-        };
-        assert!(should_stop(mode, 0));
+    fn stop_condition_refuses_when_metadata_changed() {
+        // Updated or New metadata always continues — even with zero new
+        // chapters — because the change-of-metadata bump itself is what
+        // the walk is following.
+        assert!(!should_stop(true, UpsertStatus::Updated, Some(0)));
+        assert!(!should_stop(true, UpsertStatus::New, Some(0)));
+    }
+
+    #[test]
+    fn stop_condition_refuses_when_chapter_count_unknown() {
+        // skip_chapters mode (CLI metadata-only sweep) or a
+        // logged-and-swallowed chapter sync error: we can't claim "no
+        // new chapters" from absence of evidence, so don't stop. The
+        // operator who runs metadata-only intentionally wants a full
+        // walk anyway.
+        assert!(!should_stop(true, UpsertStatus::Unchanged, None));
+    }
+
+    #[test]
+    fn stop_condition_disabled_in_recovery_mode() {
+        // was_clean = false means the previous run did not exit cleanly;
+        // the catalog past its crash point is potentially un-synced. Walk
+        // to end-of-source no matter what individual mangas report.
+        assert!(!should_stop(false, UpsertStatus::Unchanged, Some(0)));
+        assert!(!should_stop(false, UpsertStatus::Unchanged, Some(1)));
+        assert!(!should_stop(false, UpsertStatus::Updated, Some(0)));
+        assert!(!should_stop(false, UpsertStatus::New, None));
+    }
+
+    #[test]
+    fn clean_exit_when_walked_to_completion() {
+        // End-of-walk reached the catalog tail — the recovery flag may
+        // safely flip back to `true`.
+        assert!(should_mark_clean_exit(true, false));
+    }
+
+    #[test]
+    fn clean_exit_when_stop_condition_fired() {
+        // First Unchanged + 0-new-chapter manga is a complete steady-
+        // state exit: every manga newer than this point was synced, and
+        // by source-side `update_date DESC` ordering everything past
+        // this point is at least as caught-up.
+        assert!(should_mark_clean_exit(false, true));
+    }
+
+    #[test]
+    fn dirty_exit_when_neither_completion_nor_stop_fired() {
+        // The walk ended for some other reason — including the
+        // caller-imposed `hit_limit` cap, which is the regression case
+        // this test exists for. `should_mark_clean_exit` does not take
+        // `hit_limit` as a parameter, so a future edit that adds
+        // `|| hit_limit` to the inline expression in `run_metadata_pass`
+        // would need to also touch this helper, and would fail this
+        // assertion when it did.
+        assert!(!should_mark_clean_exit(false, false));
+    }
+
+    #[test]
+    fn run_scoped_seen_set_skips_duplicate_source_manga_keys() {
+        // Pins the per-ref loop contract: `contains` gates whether work
+        // runs, and `insert` only fires on the success path (after upsert).
+        // A failed ref that reappears later in the same pass must get a
+        // second chance — that's why the loop uses contains-then-insert
+        // instead of insert-and-skip-on-collision.
+        let mut seen: HashSet<String> = HashSet::new();
+
+        // First sighting of a key: not yet seen → loop proceeds.
+        assert!(!seen.contains("manga-a"), "first sighting is unseen");
+        // Simulate a failed fetch_manga: do NOT insert. Next sighting must
+        // still be considered unseen so the loop retries it.
+        assert!(!seen.contains("manga-a"), "failed key is still retryable");
+
+        // Now simulate a successful upsert — insert is called.
+        seen.insert("manga-a".to_string());
+        // Subsequent sightings of the same key are skipped.
+        assert!(seen.contains("manga-a"), "successful key is now seen");
+
+        // Distinct keys never collide.
+        assert!(!seen.contains("manga-b"), "different key independent");
+        seen.insert("manga-b".to_string());
+        assert!(seen.contains("manga-b"));
+        assert!(seen.contains("manga-a"), "first key still recorded");
     }
 }

backend/src/crawler/rate_limit.rs

@@ -98,15 +98,9 @@ impl HostRateLimiters {
     }
 }
 
-/// Extract the host (no port) from a URL string. Returns `None` for
-/// inputs without a `scheme://host` shape — those would never have
-/// reached the network layer anyway.
-fn host_of(url: &str) -> Option<String> {
-    let after_scheme = url.split_once("://")?.1;
-    let host_with_port = after_scheme.split('/').next()?;
-    let host = host_with_port.rsplit_once(':').map_or(host_with_port, |(h, _)| h);
-    (!host.is_empty()).then(|| host.to_ascii_lowercase())
-}
+// `host_of` was duplicated across session/rate_limit/pipeline; the
+// canonical version now lives in `crawler::url_utils`.
+use crate::crawler::url_utils::host_of;
 
 #[cfg(test)]
 mod tests {

backend/src/crawler/resync.rs

@@ -0,0 +1,277 @@
+//! Admin-triggered resync of a single manga's metadata + cover, or a
+//! single chapter's content.
+//!
+//! The cron tick already retries covers and chapter content on its own
+//! schedule. This module exists for the operator-controlled path:
+//! "this manga's metadata is stale / its cover never landed / this
+//! chapter is broken — pull from source now, not at the next daily
+//! tick." Wired into the admin API, never into the queue, so the work
+//! happens synchronously with the HTTP request and the admin sees the
+//! refreshed row in the response.
+//!
+//! Shares the daemon's [`BrowserManager`], rate limiter, HTTP client,
+//! and TOR controller so a force resync respects the same per-host
+//! pacing and recircuit budget the daily crawl uses — admin actions
+//! must not let an operator accidentally hammer the source.
+
+use std::sync::Arc;
+
+use anyhow::Context;
+use async_trait::async_trait;
+use sqlx::PgPool;
+use uuid::Uuid;
+
+use crate::crawler::browser_manager::BrowserManager;
+use crate::crawler::content::{self, SyncOutcome};
+use crate::crawler::pipeline;
+use crate::crawler::rate_limit::HostRateLimiters;
+use crate::crawler::safety::DownloadAllowlist;
+use crate::crawler::source::target::TargetSource;
+use crate::crawler::source::{FetchContext, Source, SourceMangaRef};
+use crate::crawler::tor::TorController;
+use crate::repo;
+use crate::repo::crawler::UpsertStatus;
+use crate::storage::Storage;
+
+/// Outcome of [`ResyncService::resync_manga`]. Mirrors the bits the
+/// admin UI cares about — was the row actually re-upserted, did the
+/// cover land — so the response can show "metadata refreshed, cover
+/// re-downloaded" or "metadata unchanged" without a second round-trip.
+#[derive(Debug, Clone, Copy)]
+pub struct MangaResyncOutcome {
+    pub manga_id: Uuid,
+    pub metadata_status: UpsertStatus,
+    pub cover_fetched: bool,
+}
+
+/// Outcome of [`ResyncService::resync_chapter`]. `Fetched(pages)` is the
+/// success case; `Skipped` means the source row was already gone or the
+/// chapter had no live source.
+#[derive(Debug, Clone)]
+pub enum ChapterResyncOutcome {
+    Fetched { chapter_id: Uuid, pages: usize },
+    Skipped { chapter_id: Uuid, reason: String },
+}
+
+/// Service exposed by the daemon to the admin API. Optional on
+/// [`AppState`] — `None` when the crawler daemon is disabled
+/// (`CRAWLER_DAEMON=false`), in which case admin handlers return 503.
+#[async_trait]
+pub trait ResyncService: Send + Sync {
+    async fn resync_manga(&self, manga_id: Uuid) -> anyhow::Result<MangaResyncOutcome>;
+    async fn resync_chapter(&self, chapter_id: Uuid) -> anyhow::Result<ChapterResyncOutcome>;
+}
+
+/// Errors with a stable shape so the API layer can map them to the
+/// right HTTP status (404 vs 422 vs 5xx). Anything else surfaces as a
+/// generic 500.
+#[derive(Debug, thiserror::Error)]
+pub enum ResyncError {
+    #[error("manga has no source to resync from")]
+    NoMangaSource,
+    #[error("chapter has no source to resync from")]
+    NoChapterSource,
+}
+
+pub struct RealResyncService {
+    pub browser_manager: Arc<BrowserManager>,
+    pub db: PgPool,
+    pub storage: Arc<dyn Storage>,
+    pub http: reqwest::Client,
+    pub rate: Arc<HostRateLimiters>,
+    pub download_allowlist: DownloadAllowlist,
+    pub max_image_bytes: usize,
+    pub tor: Option<Arc<TorController>>,
+}
+
+#[async_trait]
+impl ResyncService for RealResyncService {
+    async fn resync_manga(&self, manga_id: Uuid) -> anyhow::Result<MangaResyncOutcome> {
+        // Pick the freshest live source row. Multi-source mangas
+        // (theoretical — only one Source impl today) get the row whose
+        // `last_seen_at` is newest; soft-dropped rows are skipped.
+        let row: Option<(String, String, String)> = sqlx::query_as(
+            "SELECT source_id, source_manga_key, source_url \
+               FROM manga_sources \
+              WHERE manga_id = $1 AND dropped_at IS NULL \
+              ORDER BY last_seen_at DESC \
+              LIMIT 1",
+        )
+        .bind(manga_id)
+        .fetch_optional(&self.db)
+        .await
+        .context("look up manga_sources for resync")?;
+        let Some((_source_id, source_manga_key, source_url)) = row else {
+            return Err(ResyncError::NoMangaSource.into());
+        };
+
+        let lease = self
+            .browser_manager
+            .acquire()
+            .await
+            .context("acquire browser lease for manga resync")?;
+        let browser_ref: &chromiumoxide::Browser = &lease;
+        let ctx = FetchContext {
+            browser: browser_ref,
+            rate: &self.rate,
+            tor: self.tor.as_deref(),
+        };
+
+        // Parse chapters too — a force resync is "make this manga fully
+        // current," not just metadata. The full pipeline handles the
+        // partial-render guard for us; we replicate the same caution
+        // here by skipping the chapter sync when the parser returned
+        // empty but the manga previously had chapters.
+        let source = TargetSource::new(source_url.clone());
+        let r = SourceMangaRef {
+            source_manga_key: source_manga_key.clone(),
+            title: String::new(),
+            url: source_url.clone(),
+        };
+        let manga = source
+            .fetch_manga(&ctx, &r)
+            .await
+            .with_context(|| format!("fetch_manga during resync of {manga_id}"))?;
+
+        // Partial-render guard: same logic as run_metadata_pass.
+        let source_id = source.id();
+        if !manga.chapters.is_empty() || {
+            let prior = repo::crawler::live_chapter_count_for_source_manga(
+                &self.db,
+                source_id,
+                &source_manga_key,
+            )
+            .await
+            .unwrap_or(0);
+            prior == 0
+        } {
+            // Either the new fetch surfaced chapters, or there were
+            // none before either — chapter sync is safe to run.
+        } else {
+            tracing::warn!(
+                %manga_id,
+                source_url = %source_url,
+                "resync_manga: fetch returned empty chapters but prior count > 0; skipping chapter sync to avoid soft-drop"
+            );
+        }
+
+        let upsert = repo::crawler::upsert_manga_from_source(
+            &self.db,
+            source_id,
+            &source_url,
+            &manga,
+        )
+        .await
+        .with_context(|| format!("upsert_manga_from_source during resync of {manga_id}"))?;
+
+        // Cover refetch: force-download regardless of UpsertStatus.
+        // Admin clicked "resync" because they want the cover too.
+        let mut cover_fetched = false;
+        if let Some(cover_url) = manga.cover_url.as_deref() {
+            match pipeline::download_and_store_cover(
+                &self.db,
+                self.storage.as_ref(),
+                &self.http,
+                &self.rate,
+                &source_url,
+                upsert.manga_id,
+                cover_url,
+                &self.download_allowlist,
+                self.max_image_bytes,
+            )
+            .await
+            {
+                Ok(()) => cover_fetched = true,
+                Err(e) => tracing::warn!(
+                    %manga_id,
+                    error = ?e,
+                    "resync_manga: cover download failed"
+                ),
+            }
+        }
+
+        // Chapter sync — only when the partial-render guard above
+        // didn't bail.
+        let prior_chapter_count = repo::crawler::live_chapter_count_for_source_manga(
+            &self.db,
+            source_id,
+            &source_manga_key,
+        )
+        .await
+        .unwrap_or(0);
+        if !manga.chapters.is_empty() || prior_chapter_count == 0 {
+            match repo::crawler::sync_manga_chapters(
+                &self.db,
+                source_id,
+                upsert.manga_id,
+                &manga.chapters,
+            )
+            .await
+            {
+                Ok(diff) => tracing::info!(
+                    %manga_id,
+                    new = diff.new,
+                    refreshed = diff.refreshed,
+                    dropped = diff.dropped,
+                    "resync_manga: chapters synced"
+                ),
+                Err(e) => tracing::warn!(
+                    %manga_id,
+                    error = ?e,
+                    "resync_manga: chapter sync failed"
+                ),
+            }
+        }
+
+        drop(lease);
+        Ok(MangaResyncOutcome {
+            manga_id: upsert.manga_id,
+            metadata_status: upsert.status,
+            cover_fetched,
+        })
+    }
+
+    async fn resync_chapter(&self, chapter_id: Uuid) -> anyhow::Result<ChapterResyncOutcome> {
+        let row = repo::chapter::dispatch_target(&self.db, chapter_id)
+            .await
+            .context("look up chapter_sources for resync")?;
+        let Some((manga_id, source_url)) = row else {
+            return Err(ResyncError::NoChapterSource.into());
+        };
+
+        let lease = self
+            .browser_manager
+            .acquire()
+            .await
+            .context("acquire browser lease for chapter resync")?;
+        let result = content::sync_chapter_content(
+            &lease,
+            &self.db,
+            self.storage.as_ref(),
+            &self.http,
+            &self.rate,
+            chapter_id,
+            manga_id,
+            &source_url,
+            true,
+            &self.download_allowlist,
+            self.max_image_bytes,
+            self.tor.as_deref(),
+        )
+        .await;
+        drop(lease);
+
+        match result? {
+            SyncOutcome::Fetched { pages } => {
+                Ok(ChapterResyncOutcome::Fetched { chapter_id, pages })
+            }
+            SyncOutcome::Skipped => Ok(ChapterResyncOutcome::Skipped {
+                chapter_id,
+                reason: "chapter already had pages on disk".to_string(),
+            }),
+            SyncOutcome::SessionExpired => {
+                anyhow::bail!("source session expired — operator must refresh PHPSESSID")
+            }
+        }
+    }
+}

backend/src/crawler/safety.rs

@@ -0,0 +1,558 @@
+//! Defensive helpers for the image-download paths.
+//!
+//! Two threats this module addresses:
+//!
+//! - **SSRF**: a scraped chapter or manga page can embed an absolute
+//!   `<img src="http://10.0.0.1/...">`. The crawler runs inside the
+//!   backend container with intra-compose access to `postgres:5432`
+//!   and possibly other internal services; without a host check the
+//!   crawler would happily probe them. [`is_safe_url`] rejects
+//!   anything whose host isn't on the operator-configured allowlist,
+//!   plus any IP literal in RFC1918 / loopback / link-local / unique-
+//!   local space (including IPv4-mapped IPv6 like `::ffff:127.0.0.1`)
+//!   as a second defence for the case where an allowlisted hostname's
+//!   DNS happens to resolve to a literal private address.
+//!
+//!   **DNS rebinding is not covered.** A hostname like `cdn.allowed.com`
+//!   that *resolves* to `127.0.0.1` via hostile DNS bypasses the IP
+//!   check entirely — `is_safe_url` only inspects URL strings, not
+//!   resolved IPs. Mitigating that requires a custom reqwest resolver
+//!   that filters IPs after DNS, which would mean rebuilding reqwest's
+//!   connector. The allowlist + good operator DNS hygiene is the
+//!   realistic mitigation today.
+//!
+//! - **Unbounded download**: `Response::bytes().await` reads the full
+//!   body before returning. A malicious source serving a 10 GiB image
+//!   would fill memory and then disk. [`accumulate_capped`] streams
+//!   the body chunk-by-chunk into a [`bytes::BytesMut`] and bails as
+//!   soon as the running total exceeds the cap.
+//!
+//! Both helpers are pure-data: the SSRF check is keyed off a parsed
+//! URL string, and the byte accumulator is keyed off a generic stream.
+//! Easy to unit-test without a live network or browser.
+
+use std::net::IpAddr;
+
+use anyhow::{bail, Context};
+use bytes::BytesMut;
+use futures_util::StreamExt;
+use reqwest::Url;
+
+/// Default per-image download cap. A page image is generally <2 MiB;
+/// 32 MiB leaves headroom for high-resolution covers while still
+/// stopping a misbehaving CDN dead. Override via `CRAWLER_MAX_IMAGE_BYTES`.
+pub const DEFAULT_MAX_IMAGE_BYTES: usize = 32 * 1024 * 1024;
+
+/// Hosts that are always allowed in addition to the operator's
+/// configured allowlist. None by default — keeping the surface area
+/// minimal so the only way a URL gets through is if it matches an
+/// explicit catalog/CDN entry.
+///
+/// `allow_any` flips the host check off entirely (private-IP and
+/// scheme checks still apply). It exists for operators whose sources
+/// shard images across numbered CDN subdomains (`cdn1`, `cdn2`, …)
+/// where enumerating each host upfront is impractical. Off by default.
+#[derive(Clone, Debug, Default)]
+pub struct DownloadAllowlist {
+    hosts: Vec<String>,
+    allow_any: bool,
+}
+
+impl DownloadAllowlist {
+    pub fn new() -> Self {
+        Self {
+            hosts: Vec::new(),
+            allow_any: false,
+        }
+    }
+
+    /// Bypass the host allowlist. Scheme, localhost, and private-IP
+    /// checks in [`is_safe_url`] continue to apply — this only opens
+    /// up public hosts that weren't pre-enumerated.
+    pub fn allow_any() -> Self {
+        Self {
+            hosts: Vec::new(),
+            allow_any: true,
+        }
+    }
+
+    /// Add a host (case-insensitive match). Sub-domains are *not*
+    /// implied: pass `cdn.example.com` and `example.com` separately
+    /// if both should be reachable.
+    pub fn allow(mut self, host: impl Into<String>) -> Self {
+        let h = host.into().to_ascii_lowercase();
+        if !h.is_empty() && !self.hosts.iter().any(|existing| existing == &h) {
+            self.hosts.push(h);
+        }
+        self
+    }
+
+    pub fn is_empty(&self) -> bool {
+        self.hosts.is_empty()
+    }
+
+    pub fn contains(&self, host: &str) -> bool {
+        if self.allow_any {
+            return true;
+        }
+        let lower = host.to_ascii_lowercase();
+        self.hosts.iter().any(|h| h == &lower)
+    }
+}
+
+/// Verify a URL is safe for the crawler to fetch.
+///
+/// Rejects:
+/// - non-http(s) schemes (file://, gopher://, …),
+/// - any IP literal in private / loopback / link-local / unique-local
+///   space (defense in depth — a DNS allowlist alone wouldn't cover an
+///   attacker that places an entry like `cdn.evil` pointing at
+///   `192.168.1.1`),
+/// - the literal hostname `localhost`,
+/// - hosts that aren't on the supplied allowlist.
+///
+/// An empty allowlist rejects everything (the conservative default —
+/// callers must explicitly allow the catalog and CDN hosts).
+pub fn is_safe_url(raw_url: &str, allow: &DownloadAllowlist) -> Result<(), UrlSafetyError> {
+    let url = Url::parse(raw_url).map_err(|_| UrlSafetyError::Unparseable)?;
+    let scheme = url.scheme();
+    if scheme != "http" && scheme != "https" {
+        return Err(UrlSafetyError::BadScheme(scheme.to_string()));
+    }
+    let host = url.host_str().ok_or(UrlSafetyError::NoHost)?;
+    let lower_host = host.to_ascii_lowercase();
+    if lower_host == "localhost" {
+        return Err(UrlSafetyError::Loopback);
+    }
+    // Reject IP literals in private/loopback ranges regardless of the
+    // allowlist — if someone puts an IP literal on the allowlist they
+    // almost certainly didn't mean a private range.
+    // reqwest::Url normalises IPv6 literals as `[::1]` (brackets
+    // included) in `host_str()`. Strip the brackets before parsing.
+    let ip_candidate = lower_host
+        .strip_prefix('[')
+        .and_then(|s| s.strip_suffix(']'))
+        .unwrap_or(&lower_host);
+    if let Ok(ip) = ip_candidate.parse::<IpAddr>() {
+        if is_private_ip(&ip) {
+            return Err(UrlSafetyError::PrivateIp(ip));
+        }
+    }
+    if !allow.contains(&lower_host) {
+        return Err(UrlSafetyError::HostNotAllowed(lower_host));
+    }
+    Ok(())
+}
+
+fn is_private_ip(ip: &IpAddr) -> bool {
+    match ip {
+        IpAddr::V4(v4) => {
+            v4.is_loopback()
+                || v4.is_private()
+                || v4.is_link_local()
+                || v4.is_unspecified()
+                || v4.is_broadcast()
+                // CGNAT 100.64.0.0/10
+                || (v4.octets()[0] == 100 && (v4.octets()[1] & 0xC0) == 64)
+                // 169.254/16 link-local already covered, but 0.0.0.0/8 is special-use
+                || v4.octets()[0] == 0
+        }
+        IpAddr::V6(v6) => {
+            // IPv4-mapped IPv6 (::ffff:0:0/96): unwrap to the embedded
+            // IPv4 and recurse so `::ffff:127.0.0.1` is caught by the
+            // IPv4 loopback check rather than passing through.
+            // `Ipv6Addr::is_loopback()` only matches `::1` exactly.
+            if let Some(v4) = v6.to_ipv4_mapped() {
+                return is_private_ip(&IpAddr::V4(v4));
+            }
+            v6.is_loopback()
+                || v6.is_unspecified()
+                // fc00::/7 unique-local
+                || (v6.segments()[0] & 0xfe00) == 0xfc00
+                // fe80::/10 link-local
+                || (v6.segments()[0] & 0xffc0) == 0xfe80
+        }
+    }
+}
+
+#[derive(Debug, thiserror::Error, PartialEq, Eq)]
+pub enum UrlSafetyError {
+    #[error("URL is not parseable")]
+    Unparseable,
+    #[error("scheme {0:?} is not http or https")]
+    BadScheme(String),
+    #[error("URL is missing a host")]
+    NoHost,
+    #[error("host points at the loopback interface")]
+    Loopback,
+    #[error("host is a private/internal IP: {0}")]
+    PrivateIp(IpAddr),
+    #[error("host {0:?} is not on the crawler download allowlist")]
+    HostNotAllowed(String),
+}
+
+/// Drain a byte stream into a single buffer, bailing out as soon as
+/// the running total exceeds `max_bytes`. Generic over the stream so
+/// it's testable without a live HTTP response.
+pub async fn accumulate_capped<S, E>(stream: S, max_bytes: usize) -> anyhow::Result<bytes::Bytes>
+where
+    S: futures_core::Stream<Item = Result<bytes::Bytes, E>>,
+    E: std::error::Error + Send + Sync + 'static,
+{
+    let mut buf = BytesMut::new();
+    let mut stream = std::pin::pin!(stream);
+    while let Some(chunk) = stream.next().await {
+        let chunk = chunk.map_err(|e| anyhow::anyhow!("stream chunk: {e}"))?;
+        if buf.len().saturating_add(chunk.len()) > max_bytes {
+            bail!(
+                "response exceeds {max_bytes}-byte cap (received >{}+{})",
+                buf.len(),
+                chunk.len()
+            );
+        }
+        buf.extend_from_slice(&chunk);
+    }
+    Ok(buf.freeze())
+}
+
+/// Send `req` and stream the response into a length-limited buffer.
+/// Combines [`is_safe_url`] check + [`accumulate_capped`] so each
+/// call-site is one line.
+pub async fn fetch_bytes_capped(
+    http: &reqwest::Client,
+    url: &str,
+    referer: Option<&str>,
+    allow: &DownloadAllowlist,
+    max_bytes: usize,
+) -> anyhow::Result<bytes::Bytes> {
+    is_safe_url(url, allow).with_context(|| format!("reject unsafe URL {url}"))?;
+    let mut req = http.get(url);
+    if let Some(r) = referer {
+        req = req.header(reqwest::header::REFERER, r);
+    }
+    let resp = req
+        .send()
+        .await
+        .with_context(|| format!("GET {url}"))?
+        .error_for_status()
+        .with_context(|| format!("non-2xx for {url}"))?;
+    accumulate_capped(resp.bytes_stream(), max_bytes)
+        .await
+        .with_context(|| format!("download body for {url}"))
+}
+
+/// True when `bytes` sniffs as one of the *renderable* image formats
+/// the `/files/*key` endpoint can serve with a correct Content-Type:
+/// JPEG, PNG, WebP, GIF, AVIF. Matches the upload pipeline's
+/// whitelist in `upload::parse_image`.
+///
+/// `infer::MatcherType::Image` is intentionally NOT used — it also
+/// matches BMP, TIFF, HEIF, ICO, PSD, and JP2. Those would sniff as
+/// "image" here but [`api::files::content_type_for`] would fall back
+/// to `application/octet-stream`, prompting browsers to download
+/// instead of render. Keep the two layers aligned.
+pub fn looks_like_image(bytes: &[u8]) -> bool {
+    matches!(
+        infer::get(bytes).map(|k| k.mime_type()),
+        Some("image/jpeg" | "image/png" | "image/webp" | "image/gif" | "image/avif")
+    )
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use futures_util::stream;
+
+    fn allow_just(host: &str) -> DownloadAllowlist {
+        DownloadAllowlist::new().allow(host)
+    }
+
+    #[test]
+    fn allow_any_admits_arbitrary_public_host() {
+        // Operators who can't pre-enumerate a numbered-CDN fleet
+        // (cdn1, cdn2, …) opt into allow_any. Any public host passes.
+        let allow = DownloadAllowlist::allow_any();
+        assert!(is_safe_url("https://cdn7.random.tld/x.jpg", &allow).is_ok());
+        assert!(is_safe_url("https://anything-goes.example/", &allow).is_ok());
+    }
+
+    #[test]
+    fn allow_any_still_blocks_private_ips() {
+        // The point of the bypass is the host-allowlist check, not the
+        // SSRF defense. Private/loopback IPs stay refused.
+        let allow = DownloadAllowlist::allow_any();
+        for url in [
+            "http://10.0.0.1/",
+            "http://192.168.1.1/",
+            "http://169.254.169.254/",
+            "http://127.0.0.1/",
+            "http://[::1]/",
+            "http://[::ffff:127.0.0.1]/",
+        ] {
+            assert!(
+                matches!(
+                    is_safe_url(url, &allow).unwrap_err(),
+                    UrlSafetyError::PrivateIp(_)
+                ),
+                "allow_any must still reject {url}"
+            );
+        }
+    }
+
+    #[test]
+    fn allow_any_still_blocks_localhost() {
+        let allow = DownloadAllowlist::allow_any();
+        assert!(matches!(
+            is_safe_url("http://localhost:8080/", &allow).unwrap_err(),
+            UrlSafetyError::Loopback
+        ));
+    }
+
+    #[test]
+    fn allow_any_still_blocks_non_http_schemes() {
+        let allow = DownloadAllowlist::allow_any();
+        assert!(matches!(
+            is_safe_url("file:///etc/passwd", &allow).unwrap_err(),
+            UrlSafetyError::BadScheme(_)
+        ));
+    }
+
+    #[test]
+    fn safe_url_allows_listed_host() {
+        let allow = allow_just("cdn.example.com");
+        assert!(is_safe_url("https://cdn.example.com/img.jpg", &allow).is_ok());
+    }
+
+    #[test]
+    fn safe_url_blocks_unlisted_host() {
+        let allow = allow_just("cdn.example.com");
+        let err = is_safe_url("https://evil.example.org/img.jpg", &allow).unwrap_err();
+        assert!(matches!(err, UrlSafetyError::HostNotAllowed(h) if h == "evil.example.org"));
+    }
+
+    #[test]
+    fn safe_url_blocks_localhost_even_if_allowlisted() {
+        let allow = allow_just("localhost");
+        assert!(matches!(
+            is_safe_url("http://localhost:8080/", &allow).unwrap_err(),
+            UrlSafetyError::Loopback
+        ));
+    }
+
+    #[test]
+    fn safe_url_blocks_loopback_ipv4() {
+        let allow = allow_just("127.0.0.1");
+        assert!(matches!(
+            is_safe_url("http://127.0.0.1/", &allow).unwrap_err(),
+            UrlSafetyError::PrivateIp(_)
+        ));
+    }
+
+    #[test]
+    fn safe_url_blocks_rfc1918() {
+        let allow = allow_just("10.0.0.1");
+        for url in [
+            "http://10.0.0.1/",
+            "http://192.168.1.1/",
+            "http://172.16.0.5/",
+            "http://172.31.255.255/",
+        ] {
+            assert!(
+                matches!(
+                    is_safe_url(url, &allow).unwrap_err(),
+                    UrlSafetyError::PrivateIp(_)
+                ),
+                "should reject {url}"
+            );
+        }
+    }
+
+    #[test]
+    fn safe_url_blocks_link_local() {
+        let allow = allow_just("169.254.169.254");
+        // 169.254.169.254 is the AWS/GCP metadata service — the most
+        // dangerous SSRF target on a default cloud VM.
+        assert!(matches!(
+            is_safe_url("http://169.254.169.254/", &allow).unwrap_err(),
+            UrlSafetyError::PrivateIp(_)
+        ));
+    }
+
+    #[test]
+    fn safe_url_blocks_ipv6_loopback_and_ula() {
+        // Debug what host_str returns first — reqwest::Url normalises
+        // IPv6 literals as `[::1]` with brackets, which doesn't parse
+        // as `IpAddr` directly. The implementation strips them.
+        let allow = allow_just("[::1]");
+        let err = is_safe_url("http://[::1]/", &allow).unwrap_err();
+        assert!(
+            matches!(err, UrlSafetyError::PrivateIp(_)),
+            "expected PrivateIp, got {err:?}"
+        );
+        let allow = allow_just("[fd00::1]");
+        let err = is_safe_url("http://[fd00::1]/", &allow).unwrap_err();
+        assert!(
+            matches!(err, UrlSafetyError::PrivateIp(_)),
+            "expected PrivateIp, got {err:?}"
+        );
+    }
+
+    #[test]
+    fn safe_url_blocks_ipv4_mapped_ipv6_loopback() {
+        // `Ipv6Addr::is_loopback()` only matches `::1` exactly, so
+        // `::ffff:127.0.0.1` would slip through without the
+        // to_ipv4_mapped() unwrap in is_private_ip.
+        let allow = allow_just("[::ffff:127.0.0.1]");
+        let err = is_safe_url("http://[::ffff:127.0.0.1]/", &allow).unwrap_err();
+        assert!(
+            matches!(err, UrlSafetyError::PrivateIp(_)),
+            "expected PrivateIp, got {err:?}"
+        );
+    }
+
+    #[test]
+    fn safe_url_blocks_ipv4_mapped_ipv6_rfc1918() {
+        let allow = allow_just("[::ffff:10.0.0.1]");
+        let err = is_safe_url("http://[::ffff:10.0.0.1]/", &allow).unwrap_err();
+        assert!(matches!(err, UrlSafetyError::PrivateIp(_)));
+    }
+
+    #[test]
+    fn safe_url_blocks_non_http_schemes() {
+        let allow = allow_just("anywhere");
+        assert!(matches!(
+            is_safe_url("file:///etc/passwd", &allow).unwrap_err(),
+            UrlSafetyError::BadScheme(_)
+        ));
+        assert!(matches!(
+            is_safe_url("gopher://anywhere:70/", &allow).unwrap_err(),
+            UrlSafetyError::BadScheme(_)
+        ));
+    }
+
+    #[test]
+    fn safe_url_rejects_unparseable() {
+        let allow = allow_just("anywhere");
+        assert!(matches!(
+            is_safe_url("not a url", &allow).unwrap_err(),
+            UrlSafetyError::Unparseable
+        ));
+    }
+
+    #[test]
+    fn safe_url_empty_allowlist_rejects_everything() {
+        let allow = DownloadAllowlist::new();
+        let err = is_safe_url("https://cdn.example.com/img.jpg", &allow).unwrap_err();
+        assert!(matches!(err, UrlSafetyError::HostNotAllowed(_)));
+    }
+
+    #[test]
+    fn allowlist_matches_case_insensitively() {
+        let allow = DownloadAllowlist::new().allow("CDN.Example.COM");
+        assert!(is_safe_url("https://cdn.example.com/x.jpg", &allow).is_ok());
+        assert!(is_safe_url("https://CDN.EXAMPLE.com/x.jpg", &allow).is_ok());
+    }
+
+    #[tokio::test]
+    async fn accumulate_capped_returns_full_body_under_cap() {
+        let chunks: Vec<Result<bytes::Bytes, std::io::Error>> = vec![
+            Ok(bytes::Bytes::from_static(b"hello ")),
+            Ok(bytes::Bytes::from_static(b"world")),
+        ];
+        let s = stream::iter(chunks);
+        let out = accumulate_capped(s, 100).await.unwrap();
+        assert_eq!(out.as_ref(), b"hello world");
+    }
+
+    #[tokio::test]
+    async fn accumulate_capped_bails_past_cap() {
+        let chunks: Vec<Result<bytes::Bytes, std::io::Error>> = vec![
+            Ok(bytes::Bytes::from(vec![0u8; 50])),
+            Ok(bytes::Bytes::from(vec![0u8; 60])),
+        ];
+        let s = stream::iter(chunks);
+        let err = accumulate_capped(s, 100).await.unwrap_err();
+        assert!(err.to_string().contains("100-byte cap"));
+    }
+
+    #[tokio::test]
+    async fn accumulate_capped_surfaces_stream_errors() {
+        let chunks: Vec<Result<bytes::Bytes, std::io::Error>> = vec![
+            Ok(bytes::Bytes::from_static(b"ok")),
+            Err(std::io::Error::other("network blip")),
+        ];
+        let s = stream::iter(chunks);
+        let err = accumulate_capped(s, 100).await.unwrap_err();
+        assert!(err.to_string().contains("network blip"));
+    }
+
+    #[test]
+    fn looks_like_image_accepts_jpeg() {
+        // JPEG SOI + APP0 segment.
+        let jpeg = [0xff, 0xd8, 0xff, 0xe0, 0, 0x10, b'J', b'F', b'I', b'F'];
+        assert!(looks_like_image(&jpeg));
+    }
+
+    #[test]
+    fn looks_like_image_accepts_png() {
+        let png = [0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a, 0, 0, 0, 0];
+        assert!(looks_like_image(&png));
+    }
+
+    #[test]
+    fn looks_like_image_rejects_html_disguised_as_image() {
+        let html = b"<html><body>not an image</body></html>";
+        assert!(!looks_like_image(html));
+    }
+
+    #[test]
+    fn looks_like_image_rejects_empty() {
+        assert!(!looks_like_image(&[]));
+    }
+
+    #[test]
+    fn looks_like_image_rejects_renderable_but_unsupported_formats() {
+        // BMP, TIFF, ICO, PSD are `infer::MatcherType::Image` but the
+        // /files/*key handler doesn't have Content-Type mappings for
+        // them, so they'd be served as application/octet-stream and
+        // download instead of render. Reject at the crawler so we
+        // never land them in storage.
+        // BMP magic: "BM" + 4-byte size.
+        let bmp = [b'B', b'M', 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
+        assert!(!looks_like_image(&bmp), "BMP must be rejected (not renderable by /files)");
+
+        // TIFF little-endian magic: "II" + 42.
+        let tiff = [0x49, 0x49, 0x2a, 0x00, 0, 0, 0, 0];
+        assert!(!looks_like_image(&tiff), "TIFF must be rejected");
+
+        // ICO magic: 0x00,0x00,0x01,0x00.
+        let ico = [0x00, 0x00, 0x01, 0x00, 1, 0, 16, 16, 0, 0, 1, 0, 0x18, 0, 0x40, 0, 0, 0, 0x16, 0, 0, 0];
+        assert!(!looks_like_image(&ico), "ICO must be rejected");
+    }
+
+    #[test]
+    fn looks_like_image_accepts_webp_gif_avif() {
+        // Cover the three remaining whitelisted formats so a future
+        // tightening that drops one would fail noisily.
+        let webp = [
+            b'R', b'I', b'F', b'F',
+            0, 0, 0, 0,
+            b'W', b'E', b'B', b'P',
+            b'V', b'P', b'8', b' ',
+        ];
+        assert!(looks_like_image(&webp));
+
+        let gif = [b'G', b'I', b'F', b'8', b'7', b'a', 0, 0, 0, 0];
+        assert!(looks_like_image(&gif));
+
+        let avif = [
+            0x00, 0x00, 0x00, 0x18,
+            b'f', b't', b'y', b'p',
+            b'a', b'v', b'i', b'f',
+            0x00, 0x00, 0x00, 0x00,
+            b'm', b'i', b'f', b'1',
+            b'a', b'v', b'i', b'f',
+        ];
+        assert!(looks_like_image(&avif));
+    }
+}

backend/src/crawler/session.rs

@@ -42,36 +42,9 @@ pub enum SessionProbe {
     Transient,
 }
 
-/// Compute the cookie domain (e.g. `.example.com`) from a start URL.
-/// The leading dot makes the cookie cover every subdomain — the source
-/// often redirects between `www.` and other prefixes mid-crawl, and a
-/// host-only cookie would silently drop on the cross-subdomain hop.
-///
-/// Caveat: this takes the last two dot-labels, which is wrong for
-/// multi-part TLDs (`.co.uk`, `.com.br` would resolve to `.co.uk` and
-/// attach to every site on `.co.uk`). For those, the operator should
-/// override via `CRAWLER_COOKIE_DOMAIN` rather than relying on this
-/// function — pulling in the Public Suffix List for one knob isn't
-/// worth it yet.
-pub fn registrable_domain(url: &str) -> Option<String> {
-    let after_scheme = url.split_once("://")?.1;
-    let host_with_port = after_scheme.split('/').next()?;
-    let host = host_with_port
-        .rsplit_once(':')
-        .map_or(host_with_port, |(h, _)| h)
-        .to_ascii_lowercase();
-    if host.is_empty() {
-        return None;
-    }
-    let labels: Vec<&str> = host.split('.').filter(|l| !l.is_empty()).collect();
-    if labels.len() < 2 {
-        // Bare hostname (e.g. `localhost`) — return as-is, no leading
-        // dot. Setting `.localhost` as cookie domain is invalid.
-        return Some(host);
-    }
-    let registrable = &labels[labels.len() - 2..];
-    Some(format!(".{}", registrable.join(".")))
-}
+/// Re-export so existing callers keep working after the helper moved
+/// to `crawler::url_utils`. The body lives there.
+pub use crate::crawler::url_utils::registrable_domain;
 
 /// Inject the PHPSESSID cookie into the browser's cookie store for the
 /// catalog domain. Must be called before any navigation that depends on
@@ -127,6 +100,54 @@ pub fn classify_probe(html: &str) -> SessionProbe {
     }
 }
 
+/// Three-way classification of a chapter page response.
+///
+/// Reader pages don't render `#logo`, so [`classify_probe`] can't be
+/// reused as-is. The chapter-specific marker is `a#pic_container`
+/// (asserted by the reader-page parser at `parse_chapter_pages`).
+///
+/// Order matters: broken-page body wins over selector matches, so a
+/// transient site-wide 5xx that happens to render the avatar widget
+/// elsewhere doesn't falsely reach `Ok`.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum ChapterProbe {
+    /// `a#pic_container` present — reader rendered. Whether
+    /// `#avatar_menu` is also there is informational; if the reader
+    /// loaded the session is by definition still good.
+    Ok,
+    /// Site rendered a "logged out" or "please log in" page (no
+    /// reader, no broken-page body, and no avatar widget either).
+    /// Distinguishes the genuine expired-session case from a
+    /// transient site hiccup.
+    Unauthenticated,
+    /// Broken-page body, or reader didn't render but the user is
+    /// still logged in (avatar widget present). Caller should retry
+    /// rather than blame the session.
+    Transient,
+}
+
+pub fn classify_chapter_probe(html: &str) -> ChapterProbe {
+    if is_broken_page_body(html) {
+        return ChapterProbe::Transient;
+    }
+    let doc = scraper::Html::parse_document(html);
+    let container = scraper::Selector::parse("a#pic_container").unwrap();
+    if doc.select(&container).next().is_some() {
+        return ChapterProbe::Ok;
+    }
+    let avatar = scraper::Selector::parse("#avatar_menu").unwrap();
+    if doc.select(&avatar).next().is_some() {
+        // Logged-in user, but the reader didn't render — most likely
+        // the layout shifted or the site is serving an interstitial.
+        ChapterProbe::Transient
+    } else {
+        // No reader, no avatar, no broken-body marker — site rendered
+        // the "please log in" page, which is the genuine session-
+        // expired signal on this route.
+        ChapterProbe::Unauthenticated
+    }
+}
+
 /// In-startup retry budget for the session probe. Small but non-zero —
 /// startup hitting a 5-second site hiccup shouldn't fail the operator
 /// with "PHPSESSID expired" when the session is actually fine.
@@ -141,37 +162,123 @@ const PROBE_RETRY_DELAY: Duration = Duration::from_secs(2);
 /// limiter. The trade is worth it — failing here costs ~1s; failing 30
 /// minutes into a backfill costs 30 minutes.
 pub async fn verify_session(browser: &Browser, probe_url: &str) -> anyhow::Result<()> {
-    let mut attempt = 0u32;
+    verify_session_with_recircuit(browser, probe_url, None, 0).await
+}
+
+/// Like [`verify_session`] but, when `tor` is `Some`, signals
+/// `SIGNAL NEWNYM` between retries on transient pages AND treats
+/// `Unauthenticated` as recoverable (up to `tor_max_attempts` total
+/// probes, calling NEWNYM between each).
+///
+/// `verify_session` is `verify_session_with_recircuit(..., None, _)`,
+/// which collapses the `Unauthenticated` budget to 1 attempt — i.e.
+/// fail-fast, exactly the pre-TOR behavior.
+pub async fn verify_session_with_recircuit(
+    browser: &Browser,
+    probe_url: &str,
+    tor: Option<&crate::crawler::tor::TorController>,
+    tor_max_attempts: u32,
+) -> anyhow::Result<()> {
+    let unauth_max_attempts = if tor.is_some() { tor_max_attempts.max(1) } else { 1 };
+    run_session_probe_loop(
+        || fetch_probe_html(browser, probe_url),
+        || async {
+            if let Some(t) = tor {
+                if let Err(e) = t.new_identity().await {
+                    tracing::warn!(error = %e, "TOR NEWNYM failed; continuing with same circuit");
+                }
+            }
+        },
+        PROBE_MAX_ATTEMPTS,
+        unauth_max_attempts,
+        PROBE_RETRY_DELAY,
+        probe_url,
+    )
+    .await
+}
+
+/// Pure-over-IO loop body for the session probe. Generic over the
+/// fetch and recircuit closures so it can be unit-tested without a
+/// real browser or TOR daemon.
+///
+/// Both budgets count **total attempts**, including the first — so
+/// `transient_max_attempts = 3` allows 3 fetches and 2 recircuits
+/// between them, and `unauth_max_attempts = 1` means "fail-fast, no
+/// retry". This matches [`crate::crawler::detect::retry_on_transient`]
+/// and the content-path recircuit loop.
+///
+/// Outcomes:
+/// - `SessionProbe::Ok` → return `Ok(())`.
+/// - `SessionProbe::Unauthenticated` → recircuit + retry while
+///   under the unauth budget. After the cap, bail with the
+///   "PHPSESSID expired" diagnostic, mentioning the attempt count so
+///   a TOR-misconfig diagnosis is easier.
+/// - `SessionProbe::Transient` → same shape against the transient
+///   budget; bails with "site down or rate-limiting" after the cap.
+async fn run_session_probe_loop<F, Fut, R, RFut>(
+    mut fetch_html: F,
+    mut recircuit: R,
+    transient_max_attempts: u32,
+    unauth_max_attempts: u32,
+    retry_delay: Duration,
+    probe_url_for_msg: &str,
+) -> anyhow::Result<()>
+where
+    F: FnMut() -> Fut,
+    Fut: std::future::Future<Output = anyhow::Result<String>>,
+    R: FnMut() -> RFut,
+    RFut: std::future::Future<Output = ()>,
+{
+    debug_assert!(transient_max_attempts >= 1);
+    debug_assert!(unauth_max_attempts >= 1);
+    let mut transient_attempts = 0u32;
+    let mut unauth_attempts = 0u32;
     loop {
-        attempt += 1;
-        let html = fetch_probe_html(browser, probe_url).await?;
+        let html = fetch_html().await?;
         match classify_probe(&html) {
             SessionProbe::Ok => {
-                tracing::info!(attempt, "session probe ok — #logo + #avatar_menu present");
+                tracing::info!(
+                    transient_attempts,
+                    unauth_attempts,
+                    "session probe ok — #logo + #avatar_menu present"
+                );
                 return Ok(());
             }
             SessionProbe::Unauthenticated => {
-                return Err(anyhow!(
-                    "session probe failed — #avatar_menu not present at {probe_url} \
-                     (page rendered the normal layout); PHPSESSID is missing, expired, \
-                     or revoked. Refresh CRAWLER_PHPSESSID and re-run."
-                ));
-            }
-            SessionProbe::Transient if attempt < PROBE_MAX_ATTEMPTS => {
+                unauth_attempts += 1;
+                if unauth_attempts >= unauth_max_attempts {
+                    return Err(anyhow!(
+                        "session probe failed — #avatar_menu not present at {probe_url_for_msg} \
+                         after {unauth_attempts} attempt(s); PHPSESSID is missing, \
+                         expired, or revoked. Refresh CRAWLER_PHPSESSID and re-run."
+                    ));
+                }
                 tracing::warn!(
-                    attempt,
-                    max_attempts = PROBE_MAX_ATTEMPTS,
-                    "session probe got a transient page; retrying"
+                    attempt = unauth_attempts,
+                    max_attempts = unauth_max_attempts,
+                    "session probe Unauthenticated despite PHPSESSID; signaling TOR \
+                     NEWNYM and retrying"
                 );
-                tokio::time::sleep(PROBE_RETRY_DELAY).await;
+                recircuit().await;
+                tokio::time::sleep(retry_delay).await;
             }
             SessionProbe::Transient => {
-                return Err(anyhow!(
-                    "session probe failed — probe page at {probe_url} returned a \
-                     broken-page response after {PROBE_MAX_ATTEMPTS} attempts. \
-                     The site appears to be down or rate-limiting us; try again \
-                     later before refreshing CRAWLER_PHPSESSID."
-                ));
+                transient_attempts += 1;
+                if transient_attempts >= transient_max_attempts {
+                    return Err(anyhow!(
+                        "session probe failed — probe page at {probe_url_for_msg} returned \
+                         a broken-page response after {transient_max_attempts} attempts. \
+                         The site appears to be down or rate-limiting us; try again \
+                         later before refreshing CRAWLER_PHPSESSID."
+                    ));
+                }
+                tracing::warn!(
+                    attempt = transient_attempts,
+                    max_attempts = transient_max_attempts,
+                    "session probe got a transient page; recircuit + retry"
+                );
+                recircuit().await;
+                tokio::time::sleep(retry_delay).await;
             }
         }
     }
@@ -182,7 +289,18 @@ async fn fetch_probe_html(browser: &Browser, probe_url: &str) -> anyhow::Result<
         .new_page(probe_url)
         .await
         .with_context(|| format!("open probe page {probe_url}"))?;
-    page.wait_for_navigation().await.context("wait for nav on probe")?;
+    crate::crawler::nav::wait_for_nav(&page)
+        .await
+        .context("wait for nav on probe")?;
+    // Best-effort wait for the layout marker. Timeout is fine — the
+    // probe classifier handles a missing `#logo` as Transient anyway,
+    // and the verify loop retries on Transient.
+    let _ = crate::crawler::nav::wait_for_selector(
+        &page,
+        "#logo",
+        crate::crawler::nav::SELECTOR_TIMEOUT,
+    )
+    .await;
     let html = page.content().await.context("read probe html")?;
     page.close().await.ok();
     Ok(html)
@@ -192,44 +310,8 @@ async fn fetch_probe_html(browser: &Browser, probe_url: &str) -> anyhow::Result<
 mod tests {
     use super::*;
 
-    #[test]
-    fn registrable_domain_strips_subdomain() {
-        assert_eq!(
-            registrable_domain("https://www.target-site.com/manga/foo/").as_deref(),
-            Some(".target-site.com")
-        );
-        assert_eq!(
-            registrable_domain("https://m.example.org").as_deref(),
-            Some(".example.org")
-        );
-    }
-
-    #[test]
-    fn registrable_domain_keeps_two_label_host() {
-        assert_eq!(
-            registrable_domain("https://example.com/").as_deref(),
-            Some(".example.com")
-        );
-    }
-
-    #[test]
-    fn registrable_domain_handles_port() {
-        assert_eq!(
-            registrable_domain("http://www.foo.bar:8080/x").as_deref(),
-            Some(".foo.bar")
-        );
-    }
-
-    #[test]
-    fn registrable_domain_bare_hostname_no_leading_dot() {
-        // .localhost would be invalid as a cookie Domain.
-        assert_eq!(registrable_domain("http://localhost:5173").as_deref(), Some("localhost"));
-    }
-
-    #[test]
-    fn registrable_domain_returns_none_for_garbage() {
-        assert!(registrable_domain("not a url").is_none());
-    }
+    // registrable_domain tests live in crawler::url_utils now —
+    // it's the canonical home for that helper.
 
     #[test]
     fn classify_probe_ok_when_logo_and_avatar_present() {
@@ -273,6 +355,271 @@ mod tests {
         assert_eq!(classify_probe(""), SessionProbe::Transient);
     }
 
+    #[test]
+    fn classify_chapter_probe_ok_when_reader_rendered() {
+        let html = r#"
+            <html><body>
+              <a id="pic_container">
+                <img id="page1" src="https://cdn/1.jpg">
+              </a>
+            </body></html>
+        "#;
+        assert_eq!(classify_chapter_probe(html), ChapterProbe::Ok);
+    }
+
+    #[test]
+    fn classify_chapter_probe_unauthenticated_when_no_reader_and_no_avatar() {
+        // What a logged-out hit on a chapter URL renders: a normal
+        // site layout (header etc.) with a "please log in" body, but
+        // no reader and no avatar widget.
+        let html = r#"
+            <html><body>
+              <header><div id="logo">Catalog</div></header>
+              <main>Please log in to read this chapter.</main>
+            </body></html>
+        "#;
+        assert_eq!(
+            classify_chapter_probe(html),
+            ChapterProbe::Unauthenticated
+        );
+    }
+
+    #[test]
+    fn classify_chapter_probe_transient_when_logged_in_but_reader_missing() {
+        // Avatar shows the session is still valid; reader didn't
+        // render — site is serving an interstitial or the layout
+        // momentarily shifted. Retry, don't blame the session.
+        let html = r#"
+            <html><body>
+              <header><div id="logo">Catalog</div><div id="avatar_menu"></div></header>
+              <main>Site maintenance — back in 5 minutes.</main>
+            </body></html>
+        "#;
+        assert_eq!(classify_chapter_probe(html), ChapterProbe::Transient);
+    }
+
+    #[test]
+    fn classify_chapter_probe_transient_on_broken_page_body() {
+        let html =
+            "<html><body><p>we're sorry, the request file are not found.</p></body></html>";
+        assert_eq!(classify_chapter_probe(html), ChapterProbe::Transient);
+    }
+
+    #[test]
+    fn classify_chapter_probe_does_not_misfire_on_avatar_alone_without_reader() {
+        // Regression for the original bug: the binary
+        // find_element("#avatar_menu") check treated "no avatar" as
+        // session-expired even when a transient hiccup was the real
+        // cause. classify_chapter_probe must NOT trip on that pattern
+        // when pic_container *is* present.
+        let html = r#"
+            <html><body>
+              <a id="pic_container">
+                <img id="page1" src="https://cdn/1.jpg">
+              </a>
+            </body></html>
+        "#;
+        assert_eq!(classify_chapter_probe(html), ChapterProbe::Ok);
+    }
+
+    // --- run_session_probe_loop -----------------------------------------
+    //
+    // These tests exercise the recircuit-aware loop without a real
+    // browser. The fetch and recircuit closures are mocked over Vecs of
+    // canned outcomes / counters.
+
+    const OK_HTML: &str = r#"<html><body><div id="logo"></div><div id="avatar_menu"></div></body></html>"#;
+    const UNAUTH_HTML: &str = r#"<html><body><div id="logo"></div></body></html>"#;
+    const TRANSIENT_HTML: &str = "<html><body><p>we're sorry, the request file are not found.</p></body></html>";
+
+    #[tokio::test]
+    async fn probe_loop_ok_on_first_attempt_does_not_recircuit() {
+        let mut recircuits = 0u32;
+        let mut fetched = 0u32;
+        run_session_probe_loop(
+            || {
+                fetched += 1;
+                async { Ok(OK_HTML.to_string()) }
+            },
+            || {
+                recircuits += 1;
+                async {}
+            },
+            3,
+            3,
+            Duration::from_millis(0),
+            "https://example/probe",
+        )
+        .await
+        .expect("ok on first attempt");
+        assert_eq!(fetched, 1);
+        assert_eq!(recircuits, 0);
+    }
+
+    #[tokio::test]
+    async fn probe_loop_unauth_then_ok_when_attempt_budget_available() {
+        // Budget = 3 total attempts. Unauth on call 1, ok on call 2.
+        let mut recircuits = 0u32;
+        let mut call = 0u32;
+        run_session_probe_loop(
+            || {
+                call += 1;
+                let n = call;
+                async move {
+                    if n == 1 {
+                        Ok(UNAUTH_HTML.to_string())
+                    } else {
+                        Ok(OK_HTML.to_string())
+                    }
+                }
+            },
+            || {
+                recircuits += 1;
+                async {}
+            },
+            3,
+            3,
+            Duration::from_millis(0),
+            "https://example/probe",
+        )
+        .await
+        .expect("recovers after one recircuit");
+        assert_eq!(call, 2);
+        assert_eq!(recircuits, 1);
+    }
+
+    #[tokio::test]
+    async fn probe_loop_unauth_with_single_attempt_budget_fails_fast() {
+        // Budget = 1 total attempt = no retry (matches no-TOR behavior).
+        let mut recircuits = 0u32;
+        let mut call = 0u32;
+        let err = run_session_probe_loop(
+            || {
+                call += 1;
+                async { Ok(UNAUTH_HTML.to_string()) }
+            },
+            || {
+                recircuits += 1;
+                async {}
+            },
+            3,
+            1,
+            Duration::from_millis(0),
+            "https://example/probe",
+        )
+        .await
+        .expect_err("budget=1 → fail-fast");
+        assert_eq!(call, 1, "no retry when budget is 1");
+        assert_eq!(recircuits, 0);
+        let msg = format!("{err:#}");
+        assert!(msg.contains("Refresh CRAWLER_PHPSESSID"), "msg: {msg}");
+        assert!(msg.contains("after 1 attempt"), "expected attempt count in msg: {msg}");
+    }
+
+    #[tokio::test]
+    async fn probe_loop_unauth_after_exhausting_budget_emits_attempt_count() {
+        let mut recircuits = 0u32;
+        let mut call = 0u32;
+        let err = run_session_probe_loop(
+            || {
+                call += 1;
+                async { Ok(UNAUTH_HTML.to_string()) }
+            },
+            || {
+                recircuits += 1;
+                async {}
+            },
+            10, // transient budget irrelevant here
+            3,  // 3 attempts total, 2 recircuits between
+            Duration::from_millis(0),
+            "https://example/probe",
+        )
+        .await
+        .expect_err("exhausts unauth budget");
+        assert_eq!(call, 3);
+        assert_eq!(recircuits, 2);
+        let msg = format!("{err:#}");
+        assert!(msg.contains("after 3 attempt"), "expected attempt count in error, got: {msg}");
+    }
+
+    #[tokio::test]
+    async fn probe_loop_transient_repeats_until_max_then_errors() {
+        let mut recircuits = 0u32;
+        let mut call = 0u32;
+        let err = run_session_probe_loop(
+            || {
+                call += 1;
+                async { Ok(TRANSIENT_HTML.to_string()) }
+            },
+            || {
+                recircuits += 1;
+                async {}
+            },
+            3,
+            1,
+            Duration::from_millis(0),
+            "https://example/probe",
+        )
+        .await
+        .expect_err("transient until max → fail");
+        assert_eq!(call, 3);
+        // Recircuit fires between attempts: 3 attempts → 2 recircuits.
+        assert_eq!(recircuits, 2);
+        let msg = format!("{err:#}");
+        assert!(msg.contains("broken-page response after 3 attempts"), "msg: {msg}");
+    }
+
+    #[tokio::test]
+    async fn probe_loop_transient_then_ok_returns_ok_after_one_recircuit() {
+        let mut recircuits = 0u32;
+        let mut call = 0u32;
+        run_session_probe_loop(
+            || {
+                call += 1;
+                let n = call;
+                async move {
+                    if n == 1 {
+                        Ok(TRANSIENT_HTML.to_string())
+                    } else {
+                        Ok(OK_HTML.to_string())
+                    }
+                }
+            },
+            || {
+                recircuits += 1;
+                async {}
+            },
+            3,
+            1,
+            Duration::from_millis(0),
+            "https://example/probe",
+        )
+        .await
+        .expect("ok on second try");
+        assert_eq!(call, 2);
+        assert_eq!(recircuits, 1);
+    }
+
+    #[tokio::test]
+    async fn probe_loop_propagates_fetch_errors_immediately() {
+        let mut call = 0u32;
+        let err = run_session_probe_loop(
+            || {
+                call += 1;
+                async { Err(anyhow!("nav timeout")) }
+            },
+            || async {},
+            5,
+            5,
+            Duration::from_millis(0),
+            "https://example/probe",
+        )
+        .await
+        .expect_err("fetch error bubbles");
+        assert_eq!(call, 1);
+        assert!(format!("{err:#}").contains("nav timeout"));
+    }
+
     #[test]
     fn classify_probe_trusts_broken_body_over_stray_avatar_match() {
         // Defensive: if a broken-page body somehow contains an

backend/src/crawler/source.rs

@@ -8,19 +8,6 @@ pub mod target;
 
 use async_trait::async_trait;
 use chromiumoxide::browser::Browser;
-use serde::{Deserialize, Serialize};
-
-/// How a `discover` job should walk the source's index.
-#[derive(Clone, Copy, Debug, Serialize, Deserialize)]
-pub enum DiscoverMode {
-    /// Walk every index page from last back to first. Used for the
-    /// initial seed of a source.
-    Backfill,
-    /// Walk index pages from page 1 forward, stopping after
-    /// `stop_after_unchanged` consecutive mangas whose `metadata_hash`
-    /// matches storage. Used for the recurring cron tick.
-    Incremental { stop_after_unchanged: usize },
-}
 
 /// Pointer at a manga in the source's index, before we've fetched the
 /// detail page. The `source_manga_key` is whatever stable id the source
@@ -80,17 +67,21 @@ pub struct SourceChapter {
 pub struct FetchContext<'a> {
     pub browser: &'a Browser,
     pub rate: &'a crate::crawler::rate_limit::HostRateLimiters,
+    /// Optional TOR control-port client. When `Some`, retry helpers
+    /// signal `NEWNYM` between transient-page attempts so the next try
+    /// draws a fresh exit. `None` keeps pre-TOR behavior.
+    pub tor: Option<&'a crate::crawler::tor::TorController>,
 }
 
 /// Lazy iterator over discovered manga refs. The caller drives the
-/// walk one batch at a time, so it can break out as soon as a
-/// downstream stop condition is met (e.g. N consecutive Unchanged
-/// upserts in Incremental mode) without paying for pages it won't use.
+/// walk one batch at a time, so it can break out as soon as the
+/// downstream stop condition is met (the first manga where metadata is
+/// `Unchanged` and chapter sync reports zero new chapters) without
+/// paying for pages it won't use.
 ///
 /// Batches are typically one source-index page each. Within a batch
-/// refs are already in the right per-page order for the active mode
-/// (Backfill reverses each page to oldest-first; Incremental leaves
-/// the source's natural newest-first ordering).
+/// refs are in the source's natural newest-first ordering — the same
+/// `update_date DESC` sort that makes the stop condition meaningful.
 #[async_trait]
 pub trait DiscoverWalk: Send {
     /// Return the next batch of refs, or `Ok(None)` when the source has
@@ -107,16 +98,14 @@ pub trait Source: Send + Sync {
     /// Stable identifier — also the row key in the `sources` table.
     fn id(&self) -> &'static str;
 
-    /// Begin discovery in `mode`. Returns a walker the caller drives
-    /// page-by-page via `next_batch`. The initial page-1 probe (used
-    /// to determine `last_page` and warm the cache for sites that
-    /// can't be paged without knowing the bound) happens inside this
-    /// call, so a fresh walker is ready to yield its first batch
-    /// without further setup.
+    /// Begin discovery. Returns a walker the caller drives page-by-page
+    /// via `next_batch`. The initial page-1 probe (used to determine
+    /// `last_page` and warm the cache for sites that can't be paged
+    /// without knowing the bound) happens inside this call, so a fresh
+    /// walker is ready to yield its first batch without further setup.
     async fn discover(
         &self,
         ctx: &FetchContext<'_>,
-        mode: DiscoverMode,
     ) -> anyhow::Result<Box<dyn DiscoverWalk + Send>>;
 
     async fn fetch_manga(

backend/src/crawler/source/target.rs

@@ -7,7 +7,6 @@
 //! (`td:has(label:contains("Author:"))`) are implemented by walking
 //! the parsed tree.
 
-use std::collections::VecDeque;
 use std::time::Duration;
 
 use anyhow::Context;
@@ -15,22 +14,24 @@ use async_trait::async_trait;
 use sha2::{Digest, Sha256};
 
 use super::{
-    DiscoverMode, DiscoverWalk, FetchContext, Source, SourceChapter, SourceChapterRef,
-    SourceManga, SourceMangaRef,
+    DiscoverWalk, FetchContext, Source, SourceChapter, SourceChapterRef, SourceManga,
+    SourceMangaRef,
 };
 use crate::crawler::detect::{
-    has_logo_sentinel, is_broken_page_body, retry_on_transient, PageError,
+    has_logo_sentinel, is_broken_page_body, retry_on_transient_with_hook, PageError,
 };
+use crate::crawler::nav::{wait_for_nav, wait_for_selector, NavError, SELECTOR_TIMEOUT};
 
 /// `sources.id` value for this Source impl. Exposed as a const so the
-/// daemon can look up per-source state (e.g. `seed_completed_at`)
-/// before constructing the Source itself.
+/// daemon can look up per-source state (e.g. the recovery flag) before
+/// constructing the Source itself.
 pub const SOURCE_ID: &str = "target";
 
 /// In-loop retry budget for transient pages encountered during a single
-/// `discover` walk. Bounded small because the job system itself retries
-/// the whole `Discover` job on failure — these inline retries only need
-/// to absorb a brief site hiccup mid-walk.
+/// `discover` walk. Bounded small because the next cron tick will pick up
+/// where this run left off via the recovery flag — these inline retries
+/// only need to absorb a brief site hiccup mid-walk, not a sustained
+/// outage.
 const PAGE_TRANSIENT_RETRY_ATTEMPTS: u32 = 3;
 const PAGE_TRANSIENT_RETRY_DELAY: Duration = Duration::from_secs(2);
 
@@ -72,36 +73,25 @@ impl Source for TargetSource {
     async fn discover(
         &self,
         ctx: &FetchContext<'_>,
-        mode: DiscoverMode,
     ) -> anyhow::Result<Box<dyn DiscoverWalk + Send>> {
-        // Always visit page 1 first because that's the only way to
-        // discover `last_page`. Retry it on transient — a broken first
-        // page would otherwise abort the whole walk before we've even
-        // started.
-        let first_html = retry_on_transient(
-            || async { navigate(ctx, self.base_url.as_str()).await },
+        // Probe page 1 up front (with transient retry) for two reasons:
+        // a broken first page should abort cleanly rather than mid-walk,
+        // and the HTML is handed straight to the first `next_batch` call
+        // so the walker doesn't re-fetch it. Page count is discovered
+        // incrementally — see `TargetSourceWalker::next_batch`.
+        let first_html = retry_on_transient_with_hook(
+            || async {
+                navigate(ctx, self.base_url.as_str(), LIST_PAGE_MARKER).await
+            },
             PAGE_TRANSIENT_RETRY_ATTEMPTS,
             PAGE_TRANSIENT_RETRY_DELAY,
+            || async { recircuit_if_configured(ctx.tor).await },
         )
         .await?;
-        let last_page = {
-            let doc = scraper::Html::parse_document(&first_html);
-            parse_last_page(&doc)
-        };
-
-        let backfill = matches!(mode, DiscoverMode::Backfill);
-        let order = build_page_order(last_page, backfill);
-        tracing::info!(
-            ?mode,
-            last_page = ?last_page,
-            page_count = order.len(),
-            "walking pagination"
-        );
 
         Ok(Box::new(TargetSourceWalker {
             base_url: self.base_url.clone(),
-            backfill,
-            pages_remaining: order,
+            next_page: 1,
             first_page_html: Some(first_html),
         }))
     }
@@ -111,7 +101,17 @@ impl Source for TargetSource {
         ctx: &FetchContext<'_>,
         r: &SourceMangaRef,
     ) -> anyhow::Result<SourceManga> {
-        let html = navigate(ctx, r.url.as_str()).await?;
+        // When we'll parse the chapter table, wait for at least one
+        // chapter row to appear — that's the marker most sensitive to
+        // the post-load JS partial-render race. When we won't, fall
+        // back to the layout-level `#logo` so we still wait for the
+        // page to settle.
+        let marker = if self.parse_chapters {
+            DETAIL_PAGE_CHAPTERS_MARKER
+        } else {
+            DETAIL_PAGE_LAYOUT_MARKER
+        };
+        let html = navigate(ctx, r.url.as_str(), marker).await?;
         // Convert PageError → anyhow::Error via `?`. PageError stays
         // downcastable from the wrapped anyhow::Error so the pipeline
         // can still recognize Transient via `error.downcast_ref::<PageError>()`.
@@ -137,28 +137,19 @@ impl Source for TargetSource {
     }
 }
 
-/// Build the queue of page numbers `TargetSource::discover` will walk.
-/// Backfill is oldest-first: pages `last..=1` (within each page the
-/// walker reverses entries, since the source orders by update_date
-/// DESC). Incremental is newest-first: pages `1..=last` in natural
-/// order. If `last_page` is unknown (source surfaces no pagination)
-/// only page 1 is visited.
-fn build_page_order(last_page: Option<i32>, backfill: bool) -> VecDeque<i32> {
-    match (last_page, backfill) {
-        (None, _) => VecDeque::from([1]),
-        (Some(last), true) => (1..=last).rev().collect(),
-        (Some(last), false) => (1..=last).collect(),
-    }
-}
-
-/// Walker returned by [`TargetSource::discover`]. Pops one source-index
-/// page per `next_batch` call. Page 1's HTML is cached at construction
-/// time (the discover call needed it to read `last_page` anyway) so the
-/// batch covering page 1 doesn't re-fetch.
+/// Walker returned by [`TargetSource::discover`]. Walks pages `1..` in
+/// order, terminating as soon as a page renders cleanly with zero entries
+/// — that's the "we ran off the end of the index" signal. Page 1's HTML
+/// is cached at construction time (discover already had to fetch it for
+/// the transient probe) so the first batch doesn't re-fetch.
+///
+/// A genuinely empty `Ok(vec![])` from `parse_manga_list_from` is what
+/// stops us: the parser's `#logo` sentinel converts unrendered pages
+/// into transient errors before they reach this loop, so an empty
+/// parse result reliably means "no more entries."
 struct TargetSourceWalker {
     base_url: String,
-    backfill: bool,
-    pages_remaining: VecDeque<i32>,
+    next_page: i32,
     first_page_html: Option<String>,
 }
 
@@ -168,70 +159,104 @@ impl DiscoverWalk for TargetSourceWalker {
         &mut self,
         ctx: &FetchContext<'_>,
     ) -> anyhow::Result<Option<Vec<SourceMangaRef>>> {
-        let Some(page_num) = self.pages_remaining.pop_front() else {
-            return Ok(None);
-        };
-        let mut page_refs = if page_num == 1 {
+        let page_num = self.next_page;
+        let page_refs = if page_num == 1 {
             // Reuse the cached page-1 HTML from the initial probe. Take
-            // it (rather than clone) so a malformed page-order queue
-            // that re-visits page 1 still falls back to a real fetch.
+            // it (rather than clone) so a future re-entry that somehow
+            // revisits page 1 still falls back to a real fetch.
             match self.first_page_html.take() {
                 Some(html) => {
                     let doc = scraper::Html::parse_document(&html);
                     parse_manga_list_from(&doc)?
                 }
                 None => {
-                    retry_on_transient(
+                    retry_on_transient_with_hook(
                         || async {
-                            let html = navigate(ctx, self.base_url.as_str()).await?;
+                            let html = navigate(
+                                ctx,
+                                self.base_url.as_str(),
+                                LIST_PAGE_MARKER,
+                            )
+                            .await?;
                             let doc = scraper::Html::parse_document(&html);
                             parse_manga_list_from(&doc)
                         },
                         PAGE_TRANSIENT_RETRY_ATTEMPTS,
                         PAGE_TRANSIENT_RETRY_DELAY,
+                        || async { recircuit_if_configured(ctx.tor).await },
                     )
                     .await?
                 }
             }
         } else {
-            retry_on_transient(
+            retry_on_transient_with_hook(
                 || async {
                     let url = page_url(&self.base_url, page_num);
-                    let html = navigate(ctx, &url).await?;
+                    let html = navigate(ctx, &url, LIST_PAGE_MARKER).await?;
                     let doc = scraper::Html::parse_document(&html);
                     parse_manga_list_from(&doc)
                 },
                 PAGE_TRANSIENT_RETRY_ATTEMPTS,
                 PAGE_TRANSIENT_RETRY_DELAY,
+                || async { recircuit_if_configured(ctx.tor).await },
             )
             .await?
         };
-        if self.backfill {
-            page_refs.reverse();
-        }
         tracing::info!(page_num, count = page_refs.len(), "page walked");
+        if page_refs.is_empty() {
+            return Ok(None);
+        }
+        self.next_page += 1;
         Ok(Some(page_refs))
     }
 }
 
+/// Per-page-type markers used by `navigate`'s post-navigation wait.
+/// Each is the most specific element the parser will later look for —
+/// waiting on it closes the partial-render race (e.g. `#chapter_table`
+/// wrapper present but rows still being injected by post-load JS) that
+/// the old fixed 1s sleep masked. See [`navigate`].
+const LIST_PAGE_MARKER: &str = "#left_side .pic_list .updatesli";
+const DETAIL_PAGE_CHAPTERS_MARKER: &str = "#chapter_table td h4 a.chico";
+const DETAIL_PAGE_LAYOUT_MARKER: &str = "#logo";
+
 /// Single point of rate-limited navigation. Every Source request goes
 /// through here, so the per-host limiter map is the only knob that
 /// controls per-origin RPS. Also the choke point for transient-page
 /// detection — every fetched body is screened by
 /// [`classify_navigate_html`] before being handed to a selector.
-async fn navigate(ctx: &FetchContext<'_>, url: &str) -> Result<String, PageError> {
+///
+/// `marker` is a CSS selector the caller expects to find on the loaded
+/// page. The wait is best-effort: a timeout is **not** an error
+/// (legitimately-empty pages may never render the marker), it just
+/// caps how long we'll hold for post-load JS to finish injecting
+/// content. The parser's own sentinels and the universal broken-page
+/// body check still catch real failures.
+async fn navigate(
+    ctx: &FetchContext<'_>,
+    url: &str,
+    marker: &str,
+) -> Result<String, PageError> {
     ctx.rate.wait_for(url).await?;
     let page = ctx
         .browser
         .new_page(url)
         .await
         .map_err(|e| PageError::Other(anyhow::Error::from(e)))?;
-    page.wait_for_navigation()
-        .await
-        .map_err(|e| PageError::Other(anyhow::Error::from(e)))?;
-    // Stopgap until we wait on a specific selector per page type —
-    // gives any post-load JS a beat to finish injecting content.
-    tokio::time::sleep(Duration::from_secs(1)).await;
+    match wait_for_nav(&page).await {
+        Ok(()) => {}
+        Err(NavError::Timeout(_)) => {
+            page.close().await.ok();
+            return Err(PageError::transient("nav timeout"));
+        }
+        Err(NavError::Cdp(e)) => {
+            page.close().await.ok();
+            return Err(PageError::Other(anyhow::Error::from(e)));
+        }
+    }
+    // Best-effort wait for the page-type marker. We deliberately
+    // discard a timeout here — see fn-level doc.
+    let _ = wait_for_selector(&page, marker, SELECTOR_TIMEOUT).await;
     let html = page
         .content()
         .await
@@ -252,20 +277,20 @@ fn classify_navigate_html(html: String) -> Result<String, PageError> {
     Ok(html)
 }
 
-fn parse_last_page(doc: &scraper::Html) -> Option<i32> {
-    // Pagination links carry their page number as text. Take the
-    // numeric maximum so we don't depend on a specific layout (Prev,
-    // Next, ellipses, etc. all get filtered out by .parse).
-    let sel = scraper::Selector::parse("#left_side .pagination a").unwrap();
-    doc.select(&sel)
-        .filter_map(|a| {
-            collapse_whitespace(&a.text().collect::<String>())
-                .parse::<i32>()
-                .ok()
-        })
-        .max()
+/// Hook for [`retry_on_transient_with_hook`]: when TOR is configured,
+/// signal `NEWNYM` so the next navigation draws a fresh exit. Errors
+/// from the controller are logged and swallowed — failing to recircuit
+/// shouldn't take down the crawl, the next attempt just runs on the
+/// same circuit as before.
+async fn recircuit_if_configured(tor: Option<&crate::crawler::tor::TorController>) {
+    if let Some(t) = tor {
+        if let Err(e) = t.new_identity().await {
+            tracing::warn!(error = %e, "TOR NEWNYM failed; retrying on same circuit");
+        }
+    }
 }
 
+
 /// Substitutes the first `/N/` path segment with the target page
 /// number. Source impls that paginate via a different URL shape can
 /// override this — for the modeled site the segment is always present.
@@ -369,7 +394,7 @@ fn parse_manga_detail(
         .collect();
 
     let chapters = if include_chapters {
-        parse_chapter_list(&doc)
+        parse_chapter_list(&doc)?
     } else {
         Vec::new()
     };
@@ -427,9 +452,22 @@ fn strip_tag_count(s: &str) -> String {
     trimmed.to_string()
 }
 
-fn parse_chapter_list(doc: &scraper::Html) -> Vec<SourceChapterRef> {
+/// Parse the chapter table on a manga detail page. Returns `Transient` if
+/// `#chapter_table` isn't in the DOM at all — the table is required even
+/// for mangas with no published chapters yet (the source renders an empty
+/// `<table>`), so an absent table signals a partial render (post-load JS
+/// not done, layout drift) rather than a legitimately empty list. Without
+/// this sentinel, an empty `Vec` reaches `sync_manga_chapters` and the
+/// soft-drop branch flips every existing chapter to `dropped_at`.
+fn parse_chapter_list(doc: &scraper::Html) -> Result<Vec<SourceChapterRef>, PageError> {
+    if !has_chapter_table_sentinel(doc) {
+        return Err(PageError::transient(
+            "manga detail: #chapter_table sentinel missing",
+        ));
+    }
     let sel = scraper::Selector::parse("#chapter_table td h4 a.chico").unwrap();
-    doc.select(&sel)
+    Ok(doc
+        .select(&sel)
         .filter_map(|a| {
             let url = a.value().attr("href")?.trim().to_string();
             if url.is_empty() {
@@ -444,7 +482,16 @@ fn parse_chapter_list(doc: &scraper::Html) -> Vec<SourceChapterRef> {
                 url,
             })
         })
-        .collect()
+        .collect())
+}
+
+/// Returns true when the chapter-table container is present in the DOM.
+/// Source-specific: the target site uses `#chapter_table` as the wrapper
+/// element. Distinguishes "table is present but empty" (legit edge case
+/// for new mangas) from "table is missing entirely" (partial render).
+fn has_chapter_table_sentinel(doc: &scraper::Html) -> bool {
+    let sel = scraper::Selector::parse("#chapter_table").expect("valid selector");
+    doc.select(&sel).next().is_some()
 }
 
 fn parse_chapter_number(text: &str) -> Option<i32> {
@@ -744,7 +791,7 @@ mod tests {
             "../../../tests/fixtures/target/chapter_list_uu.html"
         );
         let doc = scraper::Html::parse_document(html);
-        let chapters = parse_chapter_list(&doc);
+        let chapters = parse_chapter_list(&doc).expect("fixture has the table");
 
         assert_eq!(chapters.len(), 15, "every row kept (notices/hiatus included)");
 
@@ -795,29 +842,6 @@ mod tests {
         assert_eq!(parse_chapter_number("Special"), None);
     }
 
-    #[test]
-    fn parse_last_page_picks_highest_pagination_link() {
-        let html = r#"
-            <div id="left_side"><div class="pagination">
-              <a href="/list/1/">Prev</a>
-              <ol>
-                <li><a href="/list/1/">1</a></li>
-                <li><a href="/list/2/">2</a></li>
-                <li><a href="/list/47/">47</a></li>
-                <li><a href="/list/2/">Next</a></li>
-              </ol>
-            </div></div>
-        "#;
-        let doc = scraper::Html::parse_document(html);
-        assert_eq!(parse_last_page(&doc), Some(47));
-    }
-
-    #[test]
-    fn parse_last_page_none_when_no_pagination() {
-        let doc = scraper::Html::parse_document("<html></html>");
-        assert!(parse_last_page(&doc).is_none());
-    }
-
     #[test]
     fn page_url_substitutes_numeric_path_segment() {
         assert_eq!(
@@ -891,9 +915,17 @@ mod tests {
 
     #[test]
     fn missing_optional_fields_parse_to_none() {
+        // Minimal but well-formed detail page: title is required, every
+        // other field is optional, but the chapter table is structural —
+        // its absence is treated as Transient (a freshly added manga
+        // renders the table empty, not absent). See
+        // `parse_chapter_list_returns_transient_when_table_missing` for
+        // the negative case.
         let html = r#"<html><body>\
             <header><div id="logo">Target</div></header>\
-            <div class="w-title"><h1>Minimal</h1></div></body></html>"#;
+            <div class="w-title"><h1>Minimal</h1></div>\
+            <table id="chapter_table"></table>\
+            </body></html>"#;
         let m = parse_manga_detail(html, "min", true).unwrap();
         assert_eq!(m.title, "Minimal");
         assert!(m.summary.is_none());
@@ -959,35 +991,62 @@ mod tests {
     }
 
     #[test]
-    fn build_page_order_backfill_is_last_to_one() {
-        // Backfill walks pages oldest-first: queue is [last, last-1, ..., 1]
-        // so popping from the front yields the last page first.
-        let order = build_page_order(Some(3), true);
-        assert_eq!(Vec::from(order), vec![3, 2, 1]);
+    fn parse_chapter_list_returns_transient_when_table_missing() {
+        // Partial render (post-load JS hadn't injected the table, layout
+        // drift, etc). Returning Vec::new() would silently soft-drop every
+        // existing chapter for the manga via sync_manga_chapters; Transient
+        // is the signal the job system retries on.
+        let html = r#"<html><body>
+            <header><div id="logo">Target</div></header>
+            <div class="w-title"><h1>Test</h1></div>
+        </body></html>"#;
+        let doc = scraper::Html::parse_document(html);
+        let err = parse_chapter_list(&doc).expect_err("expected Transient");
+        assert!(err.is_transient(), "got non-transient: {err}");
     }
 
     #[test]
-    fn build_page_order_incremental_is_one_to_last() {
-        // Incremental walks newest-first in natural source order.
-        let order = build_page_order(Some(3), false);
-        assert_eq!(Vec::from(order), vec![1, 2, 3]);
+    fn parse_chapter_list_ok_empty_when_table_present_but_no_rows() {
+        // A freshly-added manga with no chapters yet — the source renders
+        // the `<table id="chapter_table">` wrapper but no `<tr>` rows
+        // inside. Must stay distinguishable from a missing-table render.
+        let html = r#"<html><body>
+            <header><div id="logo">Target</div></header>
+            <table id="chapter_table"></table>
+        </body></html>"#;
+        let doc = scraper::Html::parse_document(html);
+        let chapters = parse_chapter_list(&doc).expect("present table is not transient");
+        assert!(chapters.is_empty());
     }
 
     #[test]
-    fn build_page_order_falls_back_to_page_one_only_without_pagination() {
-        let backfill = build_page_order(None, true);
-        assert_eq!(Vec::from(backfill), vec![1]);
-        let incremental = build_page_order(None, false);
-        assert_eq!(Vec::from(incremental), vec![1]);
+    fn parse_manga_detail_propagates_chapter_table_transient() {
+        // End-to-end: a detail page that survives the #logo sentinel but
+        // has the chapter table stripped must fail Transient at the parser
+        // boundary, not return a SourceManga with empty chapters.
+        let html = r#"<html><body>
+            <header><div id="logo">Target</div></header>
+            <div class="w-title"><h1>Test Title</h1></div>
+            <div class="cover"><img src="/cover.jpg"></div>
+            <!-- intentionally no #chapter_table -->
+        </body></html>"#;
+        let err = parse_manga_detail(html, "key", true).expect_err("expected Transient");
+        assert!(err.is_transient(), "got non-transient: {err}");
     }
 
     #[test]
-    fn build_page_order_single_page_index_yields_one_entry() {
-        // Sources with exactly one page should not yield duplicates
-        // regardless of mode.
-        let backfill = build_page_order(Some(1), true);
-        assert_eq!(Vec::from(backfill), vec![1]);
-        let incremental = build_page_order(Some(1), false);
-        assert_eq!(Vec::from(incremental), vec![1]);
+    fn parse_manga_detail_skips_chapter_sentinel_when_include_chapters_false() {
+        // Metadata-only mode (`skip_chapters` upstream) must not require
+        // the chapter table — pipeline.rs avoids calling sync_manga_chapters
+        // for these mangas, so the absent table is not a correctness issue
+        // and shouldn't surface as Transient.
+        let html = r#"<html><body>
+            <header><div id="logo">Target</div></header>
+            <div class="w-title"><h1>Test Title</h1></div>
+            <div class="cover"><img src="/cover.jpg"></div>
+        </body></html>"#;
+        let manga = parse_manga_detail(html, "key", false)
+            .expect("metadata-only parse must not require chapter table");
+        assert!(manga.chapters.is_empty());
     }
 }

backend/src/crawler/tor.rs

@@ -0,0 +1,446 @@
+//! TOR control-port client for `SIGNAL NEWNYM` ("recircuit").
+//!
+//! The crawler can be proxied through TOR (`CRAWLER_PROXY=socks5h://tor:9050`)
+//! to randomize the exit IP seen by the target site. When the target
+//! returns a "bad page" (its broken-template body, missing layout
+//! sentinel, or unauthenticated probe despite a valid PHPSESSID), it
+//! is often the current exit being rate-limited or fingerprinted rather
+//! than a real failure. Asking the local TOR daemon for a new identity
+//! over its control port (port 9051 by default) makes subsequent
+//! connections draw a fresh circuit; combined with `IsolateDestAddr`
+//! in torrc this is usually enough to clear the failure.
+//!
+//! Scope is deliberately tiny — `AUTHENTICATE` + `SIGNAL NEWNYM` over
+//! a one-shot TCP connection. No `torut` dep, no hidden-service
+//! plumbing, no event streaming.
+//!
+//! **Caveat for in-flight connections:** Chromium reuses sockets, so a
+//! `NEWNYM` only affects *new* connections (in TOR terms, new circuits).
+//! That's fine for our retry path — the next navigation opens a fresh
+//! connection. We do not try to forcibly close existing streams.
+
+use std::path::{Path, PathBuf};
+use std::time::Duration;
+
+use anyhow::{anyhow, bail, Context};
+use tokio::io::{AsyncBufReadExt, AsyncWriteExt, BufReader};
+use tokio::net::TcpStream;
+use tokio::time::timeout;
+
+/// Default control-port (`tor --defaults-torrc` ships 9051).
+const DEFAULT_CONTROL_PORT: u16 = 9051;
+/// Connect timeout — generous enough for a slow compose start, short
+/// enough that a misconfigured controller doesn't stall a crawl.
+const CONNECT_TIMEOUT: Duration = Duration::from_secs(5);
+/// Per-command read timeout. `SIGNAL NEWNYM` returns instantly on the
+/// happy path; bound it so a half-broken control port can't hang us.
+const READ_TIMEOUT: Duration = Duration::from_secs(5);
+
+/// How the controller authenticates to the control port.
+///
+/// `Cookie` is preferred for compose deploys where the auth cookie file
+/// is shared between the `tor` and `backend` containers via a named
+/// volume. `Password` is the fallback when the cookie file isn't
+/// reachable (different gid, no shared volume, etc.). `None` matches a
+/// torrc with no `CookieAuthentication 1` and no `HashedControlPassword`
+/// — useful for local experimentation, not for production.
+///
+/// `Debug` is implemented manually to redact the password (and the
+/// cookie path, which is non-sensitive but uninteresting in logs).
+/// Don't add `#[derive(Debug)]` — the controller is `?`-logged at
+/// startup and a derive would expand the password into the trace.
+#[derive(Clone)]
+pub enum TorAuth {
+    None,
+    Password(String),
+    Cookie(PathBuf),
+}
+
+impl std::fmt::Debug for TorAuth {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            TorAuth::None => f.write_str("None"),
+            TorAuth::Password(_) => f.write_str("Password(<redacted>)"),
+            TorAuth::Cookie(_) => f.write_str("Cookie(<path>)"),
+        }
+    }
+}
+
+#[derive(Debug, Clone)]
+pub struct TorController {
+    /// `host:port` string. Kept as a string (not a `SocketAddr`) so
+    /// docker-compose hostnames like `tor:9051` resolve at connect time.
+    addr: String,
+    auth: TorAuth,
+}
+
+impl TorController {
+    pub fn new(addr: impl Into<String>, auth: TorAuth) -> Self {
+        Self { addr: addr.into(), auth }
+    }
+
+    /// Build a controller from the env-config shape:
+    /// `url` (e.g. `tcp://tor:9051`, `127.0.0.1:9051`, or `tor`),
+    /// optional password, optional cookie path. Returns `Ok(None)` when
+    /// `url` is absent — that's the "TOR feature disabled" signal.
+    /// Cookie wins over password when both are set (rotates with TOR;
+    /// no secret to manage).
+    pub fn from_parts(
+        url: Option<&str>,
+        password: Option<&str>,
+        cookie_path: Option<&Path>,
+    ) -> anyhow::Result<Option<Self>> {
+        let Some(url) = url else { return Ok(None) };
+        let addr = parse_control_url(url)?;
+        let auth = match (cookie_path, password) {
+            (Some(p), _) => TorAuth::Cookie(p.to_path_buf()),
+            (None, Some(p)) => TorAuth::Password(p.to_string()),
+            (None, None) => TorAuth::None,
+        };
+        Ok(Some(Self { addr, auth }))
+    }
+
+    /// Open the control port, `AUTHENTICATE`, `SIGNAL NEWNYM`, `QUIT`.
+    /// Each invocation is a fresh connection; the controller is cheap
+    /// to clone and stateless across calls.
+    pub async fn new_identity(&self) -> anyhow::Result<()> {
+        let stream = timeout(CONNECT_TIMEOUT, TcpStream::connect(&self.addr))
+            .await
+            .with_context(|| {
+                format!("timed out connecting to TOR control port {}", self.addr)
+            })?
+            .with_context(|| format!("connect to TOR control port {}", self.addr))?;
+        let (read, mut write) = stream.into_split();
+        let mut read = BufReader::new(read);
+
+        let auth_line = self.build_auth_line().await?;
+        write_line(&mut write, &auth_line).await?;
+        timeout(READ_TIMEOUT, expect_250(&mut read))
+            .await
+            .map_err(|_| anyhow!("TOR control AUTHENTICATE timed out"))?
+            .context("AUTHENTICATE")?;
+
+        write_line(&mut write, "SIGNAL NEWNYM").await?;
+        timeout(READ_TIMEOUT, expect_250(&mut read))
+            .await
+            .map_err(|_| anyhow!("TOR control SIGNAL NEWNYM timed out"))?
+            .context("SIGNAL NEWNYM")?;
+
+        // QUIT is courtesy; ignore errors — the daemon may close the
+        // socket before our QUIT lands and that's perfectly fine.
+        let _ = write_line(&mut write, "QUIT").await;
+        // Debug-level: a busy crawl can rotate circuits many times per
+        // minute, INFO is too chatty. Failures still log at WARN.
+        tracing::debug!(addr = %self.addr, "TOR NEWNYM signaled");
+        Ok(())
+    }
+
+    async fn build_auth_line(&self) -> anyhow::Result<String> {
+        match &self.auth {
+            TorAuth::None => Ok("AUTHENTICATE".to_string()),
+            TorAuth::Password(p) => Ok(format!("AUTHENTICATE \"{}\"", escape_quoted(p))),
+            TorAuth::Cookie(path) => {
+                let bytes = tokio::fs::read(path)
+                    .await
+                    .with_context(|| format!("read TOR cookie file {}", path.display()))?;
+                Ok(format!("AUTHENTICATE {}", hex_encode(&bytes)))
+            }
+        }
+    }
+}
+
+/// Parse `tcp://host:port`, `host:port`, or bare `host` into a
+/// connect-time string. Default port is [`DEFAULT_CONTROL_PORT`].
+fn parse_control_url(url: &str) -> anyhow::Result<String> {
+    let stripped = url.strip_prefix("tcp://").unwrap_or(url);
+    if stripped.is_empty() {
+        bail!("TOR control url is empty");
+    }
+    if stripped.contains(':') {
+        Ok(stripped.to_string())
+    } else {
+        Ok(format!("{stripped}:{DEFAULT_CONTROL_PORT}"))
+    }
+}
+
+fn escape_quoted(s: &str) -> String {
+    s.replace('\\', r"\\").replace('"', r#"\""#)
+}
+
+fn hex_encode(bytes: &[u8]) -> String {
+    let mut s = String::with_capacity(bytes.len() * 2);
+    for b in bytes {
+        s.push_str(&format!("{b:02x}"));
+    }
+    s
+}
+
+async fn write_line<W: tokio::io::AsyncWrite + Unpin>(
+    w: &mut W,
+    line: &str,
+) -> anyhow::Result<()> {
+    w.write_all(line.as_bytes()).await?;
+    w.write_all(b"\r\n").await?;
+    w.flush().await?;
+    Ok(())
+}
+
+/// Drain a TOR control reply, accepting only status `250`. Handles
+/// the protocol's three line forms: `XYZ ...` (single/end), `XYZ-...`
+/// (continuation), `XYZ+...` (data block ended by a lone `.`). Our
+/// commands only ever produce single-line `250 OK`, but we honor the
+/// continuation forms so a future torrc that adds events / banners
+/// doesn't confuse the parser.
+async fn expect_250<R: AsyncBufReadExt + Unpin>(r: &mut R) -> anyhow::Result<()> {
+    loop {
+        let mut line = String::new();
+        let n = r.read_line(&mut line).await?;
+        if n == 0 {
+            bail!("TOR control port closed connection mid-reply");
+        }
+        let trimmed = line.trim_end_matches(['\r', '\n']);
+        if trimmed.len() < 4 {
+            bail!("malformed TOR control reply: {trimmed:?}");
+        }
+        let (code, rest) = trimmed.split_at(3);
+        if code != "250" {
+            bail!("TOR control replied {trimmed:?}");
+        }
+        let sep = rest.as_bytes()[0];
+        match sep {
+            b' ' => return Ok(()),
+            b'-' => continue,
+            b'+' => {
+                // Data block — read until a line consisting of only ".".
+                loop {
+                    let mut data = String::new();
+                    let n = r.read_line(&mut data).await?;
+                    if n == 0 {
+                        bail!("TOR control port closed mid-data-block");
+                    }
+                    if data.trim_end_matches(['\r', '\n']) == "." {
+                        break;
+                    }
+                }
+            }
+            _ => bail!("malformed TOR control reply separator: {trimmed:?}"),
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::sync::{Arc, Mutex};
+    use tokio::io::AsyncWriteExt;
+    use tokio::net::TcpListener;
+
+    /// Spawn a mock control port that responds to each \r\n-terminated
+    /// inbound line with the next entry from `replies`. Each reply has
+    /// its own `\r\n` appended. Records received lines into `recorder`.
+    /// After `replies.len()` exchanges the task drops the socket — this
+    /// matches the real TOR behavior for QUIT (close after acking).
+    async fn spawn_mock(
+        replies: Vec<&'static str>,
+        recorder: Arc<Mutex<Vec<String>>>,
+    ) -> String {
+        let listener = TcpListener::bind("127.0.0.1:0").await.unwrap();
+        let addr = listener.local_addr().unwrap().to_string();
+        tokio::spawn(async move {
+            let (sock, _) = listener.accept().await.unwrap();
+            let (r, mut w) = sock.into_split();
+            let mut r = BufReader::new(r);
+            for reply in replies {
+                let mut line = String::new();
+                let n = r.read_line(&mut line).await.unwrap_or(0);
+                if n == 0 {
+                    return;
+                }
+                recorder
+                    .lock()
+                    .unwrap()
+                    .push(line.trim_end_matches(['\r', '\n']).to_string());
+                w.write_all(reply.as_bytes()).await.unwrap();
+                w.write_all(b"\r\n").await.unwrap();
+                w.flush().await.unwrap();
+            }
+        });
+        addr
+    }
+
+    #[tokio::test]
+    async fn password_auth_then_newnym_writes_expected_sequence() {
+        let recorder = Arc::new(Mutex::new(Vec::new()));
+        // Two replies: AUTHENTICATE then SIGNAL NEWNYM. QUIT is
+        // fire-and-forget; the mock dropping the socket is the
+        // expected real-world behavior.
+        let addr =
+            spawn_mock(vec!["250 OK", "250 OK"], Arc::clone(&recorder)).await;
+        let controller = TorController::new(addr, TorAuth::Password("secret".into()));
+        controller.new_identity().await.expect("new_identity ok");
+        let recorded = recorder.lock().unwrap().clone();
+        assert_eq!(recorded.first().map(String::as_str), Some("AUTHENTICATE \"secret\""));
+        assert_eq!(recorded.get(1).map(String::as_str), Some("SIGNAL NEWNYM"));
+    }
+
+    #[tokio::test]
+    async fn cookie_auth_hex_encodes_file_bytes() {
+        let tmp = tempfile::NamedTempFile::new().unwrap();
+        let cookie: Vec<u8> = (0u8..32).collect();
+        std::fs::write(tmp.path(), &cookie).unwrap();
+        let recorder = Arc::new(Mutex::new(Vec::new()));
+        let addr =
+            spawn_mock(vec!["250 OK", "250 OK"], Arc::clone(&recorder)).await;
+        let controller =
+            TorController::new(addr, TorAuth::Cookie(tmp.path().to_path_buf()));
+        controller.new_identity().await.expect("new_identity ok");
+        let recorded = recorder.lock().unwrap().clone();
+        let expected_hex: String = cookie.iter().map(|b| format!("{b:02x}")).collect();
+        assert_eq!(
+            recorded.first().map(String::as_str),
+            Some(format!("AUTHENTICATE {expected_hex}").as_str())
+        );
+    }
+
+    #[tokio::test]
+    async fn no_auth_sends_bare_authenticate() {
+        let recorder = Arc::new(Mutex::new(Vec::new()));
+        let addr =
+            spawn_mock(vec!["250 OK", "250 OK"], Arc::clone(&recorder)).await;
+        let controller = TorController::new(addr, TorAuth::None);
+        controller.new_identity().await.expect("new_identity ok");
+        let recorded = recorder.lock().unwrap().clone();
+        assert_eq!(recorded.first().map(String::as_str), Some("AUTHENTICATE"));
+    }
+
+    #[tokio::test]
+    async fn non_250_reply_returns_err_with_reply_text() {
+        let recorder = Arc::new(Mutex::new(Vec::new()));
+        let addr = spawn_mock(
+            vec!["515 Bad authentication"],
+            Arc::clone(&recorder),
+        )
+        .await;
+        let controller =
+            TorController::new(addr, TorAuth::Password("wrong".into()));
+        let err = controller.new_identity().await.expect_err("should fail");
+        let msg = format!("{err:#}");
+        assert!(msg.contains("515"), "expected 515 in error, got: {msg}");
+    }
+
+    #[tokio::test]
+    async fn closed_connection_mid_reply_is_an_error() {
+        // Listener accepts the AUTH line then drops without replying —
+        // this exercises the EOF-mid-reply path in expect_250 (rather
+        // than tor's own error replies which are covered elsewhere).
+        let listener = TcpListener::bind("127.0.0.1:0").await.unwrap();
+        let addr = listener.local_addr().unwrap().to_string();
+        tokio::spawn(async move {
+            if let Ok((sock, _)) = listener.accept().await {
+                let (r, _w) = sock.into_split();
+                let mut r = BufReader::new(r);
+                let mut line = String::new();
+                let _ = r.read_line(&mut line).await; // read AUTH, ignore
+                // Drop _w (and the read half via scope exit) so the
+                // peer sees an immediate EOF on the next read.
+            }
+        });
+        let controller = TorController::new(addr, TorAuth::None);
+        let err = controller.new_identity().await.expect_err("should fail");
+        let msg = format!("{err:#}");
+        assert!(
+            msg.contains("closed connection"),
+            "expected EOF-mid-reply error, got: {msg}"
+        );
+    }
+
+    #[tokio::test]
+    async fn multi_line_250_continuation_is_accepted() {
+        let recorder = Arc::new(Mutex::new(Vec::new()));
+        // AUTHENTICATE reply uses the `250-...\r\n250 OK\r\n` form.
+        // Single reply string contains the whole multi-line response.
+        let addr = spawn_mock(
+            vec!["250-banner=foo\r\n250 OK", "250 OK"],
+            Arc::clone(&recorder),
+        )
+        .await;
+        let controller = TorController::new(addr, TorAuth::None);
+        controller.new_identity().await.expect("new_identity ok");
+    }
+
+    #[test]
+    fn from_parts_returns_none_when_url_unset() {
+        let c = TorController::from_parts(None, None, None).unwrap();
+        assert!(c.is_none());
+    }
+
+    #[test]
+    fn from_parts_prefers_cookie_over_password() {
+        let c = TorController::from_parts(
+            Some("tor:9051"),
+            Some("pw"),
+            Some(Path::new("/var/lib/tor/control_auth_cookie")),
+        )
+        .unwrap()
+        .expect("controller built");
+        assert!(matches!(c.auth, TorAuth::Cookie(_)));
+    }
+
+    #[test]
+    fn from_parts_falls_back_to_password_without_cookie() {
+        let c = TorController::from_parts(Some("tor:9051"), Some("pw"), None)
+            .unwrap()
+            .expect("controller built");
+        assert!(matches!(c.auth, TorAuth::Password(p) if p == "pw"));
+    }
+
+    #[test]
+    fn parse_control_url_accepts_tcp_scheme() {
+        assert_eq!(parse_control_url("tcp://127.0.0.1:9051").unwrap(), "127.0.0.1:9051");
+    }
+
+    #[test]
+    fn parse_control_url_defaults_port_when_omitted() {
+        assert_eq!(parse_control_url("tor").unwrap(), "tor:9051");
+    }
+
+    #[test]
+    fn parse_control_url_passes_through_host_port() {
+        assert_eq!(parse_control_url("tor:9999").unwrap(), "tor:9999");
+    }
+
+    #[test]
+    fn parse_control_url_rejects_empty() {
+        assert!(parse_control_url("").is_err());
+        assert!(parse_control_url("tcp://").is_err());
+    }
+
+    #[test]
+    fn escape_quoted_handles_quotes_and_backslashes() {
+        assert_eq!(escape_quoted(r#"a"b\c"#), r#"a\"b\\c"#);
+    }
+
+    #[test]
+    fn debug_format_redacts_password_and_cookie_path() {
+        // Regression: app.rs / bin/crawler.rs log the controller at
+        // startup via `tracing::info!(?t, ...)`. A derived Debug on
+        // TorAuth would expand TorAuth::Password(p) and leak the
+        // plaintext into logs.
+        let c = TorController::new("tor:9051", TorAuth::Password("super-secret".into()));
+        let dbg = format!("{c:?}");
+        assert!(!dbg.contains("super-secret"), "password leaked: {dbg}");
+        assert!(dbg.contains("<redacted>"), "expected <redacted>, got: {dbg}");
+
+        let c = TorController::new(
+            "tor:9051",
+            TorAuth::Cookie("/var/lib/tor/control_auth_cookie".into()),
+        );
+        let dbg = format!("{c:?}");
+        assert!(!dbg.contains("control_auth_cookie"), "cookie path leaked: {dbg}");
+    }
+
+    #[test]
+    fn hex_encode_zero_pads_low_bytes() {
+        assert_eq!(hex_encode(&[0x00, 0x0f, 0xff]), "000fff");
+    }
+}

backend/src/crawler/url_utils.rs

@@ -0,0 +1,244 @@
+//! Centralised URL helpers for the crawler subsystem.
+//!
+//! Three near-identical hand-rolled URL parsers used to live in
+//! `crawler::session`, `crawler::rate_limit`, and `crawler::pipeline`
+//! respectively, each with subtly different edge-case behaviour
+//! around port handling and IPv6 literals. They're consolidated here
+//! so the divergence can't drift again.
+//!
+//! The hand-rolled implementations are kept intentionally — they
+//! preserve the exact semantics every existing test pins. A future
+//! refactor can switch to `reqwest::Url` if it can be done without
+//! changing those semantics.
+
+/// Lowercased host (no port). Returns `None` for inputs without a
+/// `scheme://host` shape — those would never have reached the network
+/// layer anyway. Used by the per-host rate limiter as its bucket key.
+///
+/// IPv6 literals are kept in their `[::1]` bracketed form so the
+/// `rsplit_once(':')` port-stripping logic doesn't split inside the
+/// address (e.g. `https://[::1]/foo` used to return `"[:"` because
+/// the rightmost `:` is inside the literal). Buckets keyed by
+/// `[::1]` vs `::1` are still uniquely-per-host; the brackets are
+/// cosmetic.
+pub fn host_of(url: &str) -> Option<String> {
+    let after_scheme = url.split_once("://")?.1;
+    let host_with_port = after_scheme.split('/').next()?;
+    let host = if host_with_port.starts_with('[') {
+        // IPv6 literal: keep through the closing bracket. There may
+        // be a trailing `:port` after `]`; strip only that.
+        match host_with_port.rfind(']') {
+            Some(end) => &host_with_port[..=end],
+            None => host_with_port,
+        }
+    } else {
+        // Hostnames and IPv4 literals: trailing `:port` (if any) is
+        // after the last `:`.
+        host_with_port
+            .rsplit_once(':')
+            .map_or(host_with_port, |(h, _)| h)
+    };
+    (!host.is_empty()).then(|| host.to_ascii_lowercase())
+}
+
+/// `scheme://host` with no path or port stripping. Used by the metadata
+/// pass to seed `sources.base_url` from `CRAWLER_START_URL`.
+pub fn origin_of(url: &str) -> Option<String> {
+    let (scheme, rest) = url.split_once("://")?;
+    let host = rest.split('/').next()?;
+    Some(format!("{scheme}://{host}"))
+}
+
+/// Approximate registrable-domain calculation: take the last two
+/// dot-labels of the host, prefix with `.`. Used to set a parent-
+/// domain cookie so the catalog's `www.` / `m.` redirects don't drop
+/// the cookie mid-crawl.
+///
+/// Caveat: wrong for multi-part TLDs (`.co.uk`, `.com.br`). The
+/// operator can override via `CRAWLER_COOKIE_DOMAIN`; pulling in the
+/// Public Suffix List for one knob isn't worth it yet.
+///
+/// Bare hostnames (e.g. `localhost`) return the host as-is, with no
+/// leading dot — setting `.localhost` as a cookie domain is invalid.
+/// IPv6 literals (e.g. `[::1]`) are returned bracketed and unchanged;
+/// the browser will reject them as a cookie `Domain` anyway, but the
+/// representation stays sensible. Same `starts_with('[')` branch as
+/// [`host_of`] for consistent IPv6 handling across the module.
+pub fn registrable_domain(url: &str) -> Option<String> {
+    let after_scheme = url.split_once("://")?.1;
+    let host_with_port = after_scheme.split('/').next()?;
+    let host_str = if host_with_port.starts_with('[') {
+        // IPv6 literal: keep through the closing bracket; an optional
+        // `:port` follows `]`.
+        match host_with_port.rfind(']') {
+            Some(end) => &host_with_port[..=end],
+            None => host_with_port,
+        }
+    } else {
+        host_with_port
+            .rsplit_once(':')
+            .map_or(host_with_port, |(h, _)| h)
+    };
+    let host = host_str.to_ascii_lowercase();
+    if host.is_empty() {
+        return None;
+    }
+    let labels: Vec<&str> = host.split('.').filter(|l| !l.is_empty()).collect();
+    if labels.len() < 2 {
+        return Some(host);
+    }
+    let registrable = &labels[labels.len() - 2..];
+    Some(format!(".{}", registrable.join(".")))
+}
+
+/// Normalise a SOCKS proxy URL for Chromium's `--proxy-server=` flag.
+///
+/// reqwest accepts both `socks5://` (resolve locally) and
+/// `socks5h://` (resolve via the SOCKS server — important when the
+/// proxy is TOR and we don't want the host's resolver to see the
+/// target hostname). Chromium does **not** know the `socks5h` scheme
+/// and refuses navigations with `ERR_NO_SUPPORTED_PROXIES`. It
+/// already sends destination hostnames over SOCKS5 by default
+/// regardless, so stripping the `h` is a pure scheme rename — the
+/// remote-DNS behaviour is preserved.
+///
+/// Non-SOCKS schemes pass through unchanged.
+pub fn chromium_proxy_arg(proxy: &str) -> String {
+    if let Some(rest) = proxy.strip_prefix("socks5h://") {
+        format!("socks5://{rest}")
+    } else {
+        proxy.to_string()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn host_of_strips_port_and_lowercases() {
+        assert_eq!(
+            host_of("https://CDN.Example.com:443/x").as_deref(),
+            Some("cdn.example.com")
+        );
+        assert_eq!(host_of("http://localhost/").as_deref(), Some("localhost"));
+        assert_eq!(host_of("not a url"), None);
+    }
+
+    #[test]
+    fn host_of_keeps_bracketed_ipv6_literal_intact() {
+        // Regression: the old impl rsplit_once(':')'d the IPv6 address,
+        // returning "[:" instead of "[::1]". A real IPv6 source would
+        // silently get a wrong rate-limit bucket key.
+        assert_eq!(host_of("https://[::1]/").as_deref(), Some("[::1]"));
+        assert_eq!(host_of("https://[::1]:8080/").as_deref(), Some("[::1]"));
+        assert_eq!(
+            host_of("https://[2001:db8::1]/foo").as_deref(),
+            Some("[2001:db8::1]")
+        );
+        assert_eq!(
+            host_of("https://[2001:db8::1]:443/foo").as_deref(),
+            Some("[2001:db8::1]")
+        );
+    }
+
+    #[test]
+    fn origin_of_returns_scheme_and_host() {
+        assert_eq!(
+            origin_of("https://example.com/some/path?q=1").as_deref(),
+            Some("https://example.com")
+        );
+        assert_eq!(origin_of("garbage"), None);
+    }
+
+    #[test]
+    fn registrable_domain_strips_subdomain() {
+        assert_eq!(
+            registrable_domain("https://www.target-site.com/manga/foo/").as_deref(),
+            Some(".target-site.com")
+        );
+        assert_eq!(
+            registrable_domain("https://m.example.org").as_deref(),
+            Some(".example.org")
+        );
+    }
+
+    #[test]
+    fn registrable_domain_keeps_two_label_host() {
+        assert_eq!(
+            registrable_domain("https://example.com/").as_deref(),
+            Some(".example.com")
+        );
+    }
+
+    #[test]
+    fn registrable_domain_handles_port() {
+        assert_eq!(
+            registrable_domain("http://www.foo.bar:8080/x").as_deref(),
+            Some(".foo.bar")
+        );
+    }
+
+    #[test]
+    fn registrable_domain_bare_hostname_no_leading_dot() {
+        assert_eq!(
+            registrable_domain("http://localhost:5173").as_deref(),
+            Some("localhost")
+        );
+    }
+
+    #[test]
+    fn registrable_domain_returns_none_for_garbage() {
+        assert!(registrable_domain("not a url").is_none());
+    }
+
+    #[test]
+    fn registrable_domain_keeps_bracketed_ipv6_literal_intact() {
+        // Symmetric with host_of's IPv6 fix. The cookie-domain code
+        // won't accept an IP as a `Domain` value, but the function
+        // should at least return a sensible representation rather
+        // than the truncated `"[:"` the old port-stripper produced.
+        assert_eq!(
+            registrable_domain("https://[::1]/").as_deref(),
+            Some("[::1]")
+        );
+        assert_eq!(
+            registrable_domain("https://[::1]:8080/").as_deref(),
+            Some("[::1]")
+        );
+        assert_eq!(
+            registrable_domain("https://[2001:db8::1]/foo").as_deref(),
+            Some("[2001:db8::1]")
+        );
+    }
+
+    #[test]
+    fn chromium_proxy_arg_strips_socks5h_to_socks5() {
+        // Regression: passing socks5h:// to Chromium yields
+        // ERR_NO_SUPPORTED_PROXIES at navigation time.
+        assert_eq!(
+            chromium_proxy_arg("socks5h://127.0.0.1:9050"),
+            "socks5://127.0.0.1:9050"
+        );
+        assert_eq!(
+            chromium_proxy_arg("socks5h://tor:9050"),
+            "socks5://tor:9050"
+        );
+    }
+
+    #[test]
+    fn chromium_proxy_arg_passes_socks5_unchanged() {
+        assert_eq!(
+            chromium_proxy_arg("socks5://127.0.0.1:9050"),
+            "socks5://127.0.0.1:9050"
+        );
+    }
+
+    #[test]
+    fn chromium_proxy_arg_passes_non_socks_unchanged() {
+        assert_eq!(
+            chromium_proxy_arg("http://proxy.example:8080"),
+            "http://proxy.example:8080"
+        );
+    }
+}

backend/src/domain/admin_audit.rs

@@ -0,0 +1,15 @@
+use chrono::{DateTime, Utc};
+use serde::Serialize;
+use sqlx::FromRow;
+use uuid::Uuid;
+
+#[derive(Debug, Clone, Serialize, FromRow)]
+pub struct AdminAuditEntry {
+    pub id: Uuid,
+    pub actor_user_id: Option<Uuid>,
+    pub action: String,
+    pub target_kind: String,
+    pub target_id: Option<Uuid>,
+    pub payload: serde_json::Value,
+    pub at: DateTime<Utc>,
+}

backend/src/domain/mod.rs

@@ -1,3 +1,4 @@
+pub mod admin_audit;
 pub mod api_token;
 pub mod author;
 pub mod bookmark;
@@ -9,11 +10,13 @@ pub mod page;
 pub mod patch;
 pub mod read_progress;
 pub mod session;
+pub mod sync_state;
 pub mod tag;
 pub mod upload_entry;
 pub mod user;
 pub mod user_preferences;
 
+pub use admin_audit::AdminAuditEntry;
 pub use api_token::ApiToken;
 pub use author::{Author, AuthorRef, AuthorWithCount};
 pub use bookmark::{Bookmark, BookmarkSummary};
@@ -25,6 +28,7 @@ pub use page::Page;
 pub use patch::Patch;
 pub use read_progress::{ReadProgress, ReadProgressForManga, ReadProgressSummary};
 pub use session::Session;
+pub use sync_state::{ChapterSyncState, MangaSyncState};
 pub use tag::{Tag, TagRef};
 pub use upload_entry::UploadEntry;
 pub use user::User;

backend/src/domain/sync_state.rs

@@ -0,0 +1,48 @@
+//! Sync-state enums derived per-manga / per-chapter from `manga_sources`,
+//! `chapter_sources`, and `crawler_jobs` at query time. No state column
+//! is persisted on `mangas` / `chapters` — see `repo::admin_view` for the
+//! derivation rules and priority order.
+
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, sqlx::Type)]
+#[sqlx(type_name = "text", rename_all = "snake_case")]
+#[serde(rename_all = "snake_case")]
+pub enum MangaSyncState {
+    /// A `sync_manga` or `sync_chapter_list` job is currently
+    /// pending or running for this manga.
+    InProgress,
+    /// At least one `manga_sources` row exists for this manga and ALL of
+    /// them have `dropped_at IS NOT NULL` — every source we know about
+    /// has stopped surfacing it.
+    Dropped,
+    /// Default healthy state: at least one live source row OR the manga
+    /// was user-uploaded (no `manga_sources` rows at all).
+    Synced,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, sqlx::Type)]
+#[sqlx(type_name = "text", rename_all = "snake_case")]
+#[serde(rename_all = "snake_case")]
+pub enum ChapterSyncState {
+    /// A `sync_chapter_content` job is currently pending or running for
+    /// this chapter (the 0014 dedup index guarantees at most one).
+    Downloading,
+    /// At least one `chapter_sources` row exists AND all of them are
+    /// `dropped_at IS NOT NULL`.
+    Dropped,
+    /// `page_count = 0` AND a `dead` `sync_chapter_content` job exists
+    /// for this chapter. Checked BEFORE `NotDownloaded` so the more
+    /// informative "we tried and it died" state wins over "we never
+    /// got around to it". Does NOT fire when `page_count > 0`, because
+    /// pages on disk mean the chapter IS synced regardless of historical
+    /// job failures — see the priority comment in `repo::admin_view`.
+    Failed,
+    /// `page_count = 0` and no in-flight or failed job — the chapter
+    /// row exists but content has never been downloaded.
+    NotDownloaded,
+    /// `page_count > 0` — content has been downloaded at some point.
+    /// Reaped `done` jobs in `crawler_jobs` mean we can't read this from
+    /// the job table, so `page_count` is the durable truth.
+    Synced,
+}

backend/src/domain/user.rs

@@ -10,4 +10,5 @@ pub struct User {
     #[serde(skip)]
     pub password_hash: String,
     pub created_at: DateTime<Utc>,
+    pub is_admin: bool,
 }

backend/src/error.rs

@@ -21,6 +21,16 @@ pub enum AppError {
     PayloadTooLarge(String),
     #[error("unsupported media type: {0}")]
     UnsupportedMediaType(String),
+    /// 503 — a feature is currently unavailable, distinct from a 5xx
+    /// internal error. Used when admin actions require the crawler
+    /// daemon but it's been disabled (`CRAWLER_DAEMON=false`).
+    #[error("service unavailable: {0}")]
+    ServiceUnavailable(String),
+    /// 429 with an optional `Retry-After` header value (in seconds).
+    #[error("too many requests")]
+    TooManyRequests {
+        retry_after_secs: Option<u64>,
+    },
     /// Semantic per-field validation failure. `details` is rendered into the
     /// envelope so the client can highlight the bad field(s).
     #[error("validation failed")]
@@ -51,6 +61,8 @@ impl AppError {
             AppError::Conflict(_) => "conflict",
             AppError::PayloadTooLarge(_) => "payload_too_large",
             AppError::UnsupportedMediaType(_) => "unsupported_media_type",
+            AppError::ServiceUnavailable(_) => "service_unavailable",
+            AppError::TooManyRequests { .. } => "too_many_requests",
             AppError::ValidationFailed { .. } => "validation_failed",
             AppError::Database(sqlx::Error::RowNotFound) => "not_found",
             AppError::Database(_) => "internal_error",
@@ -79,6 +91,34 @@ impl IntoResponse for AppError {
             AppError::UnsupportedMediaType(msg) => {
                 (StatusCode::UNSUPPORTED_MEDIA_TYPE, msg.clone(), None)
             }
+            AppError::ServiceUnavailable(msg) => {
+                (StatusCode::SERVICE_UNAVAILABLE, msg.clone(), None)
+            }
+            AppError::TooManyRequests { retry_after_secs } => {
+                // Emit `Retry-After: N` (RFC 6585 §4) so a well-behaved
+                // client can back off correctly. Done by building the
+                // response by hand below — the `(status, headers,
+                // body)` tuple shape doesn't fit the standard
+                // `(status, body)` IntoResponse path for the other
+                // variants.
+                let body = json!({
+                    "error": {
+                        "code": code,
+                        "message": "too many requests; slow down",
+                    }
+                });
+                let mut resp = (StatusCode::TOO_MANY_REQUESTS, Json(body)).into_response();
+                if let Some(secs) = retry_after_secs {
+                    // `HeaderValue: From<u64>` skips both the
+                    // intermediate `String` allocation and the
+                    // fallible-by-shape `from_str` path.
+                    resp.headers_mut().insert(
+                        axum::http::header::RETRY_AFTER,
+                        axum::http::HeaderValue::from(*secs),
+                    );
+                }
+                return resp;
+            }
             AppError::ValidationFailed { message, details } => (
                 StatusCode::UNPROCESSABLE_ENTITY,
                 message.clone(),

backend/src/main.rs

@@ -1,12 +1,21 @@
 use std::net::SocketAddr;
+use std::time::Duration;
 use tracing_subscriber::EnvFilter;
 
+/// Upper bound on how long we're willing to wait for the crawler daemon
+/// to drain before letting `main` return. Without it a wedged background
+/// task (e.g. a chromiumoxide handler stuck on a dead WS) blocks the
+/// process from exiting after Ctrl-C / SIGTERM.
+const CRAWLER_SHUTDOWN_TIMEOUT: Duration = Duration::from_secs(5);
+
 #[tokio::main]
 async fn main() -> anyhow::Result<()> {
     dotenvy::dotenv().ok();
     tracing_subscriber::fmt()
         .with_env_filter(
-            EnvFilter::try_from_default_env().unwrap_or_else(|_| "info,mangalord=debug".into()),
+            EnvFilter::try_from_default_env().unwrap_or_else(|_| {
+                "info,mangalord=debug,chromiumoxide::conn=off,chromiumoxide::handler=off".into()
+            }),
         )
         .init();
 
@@ -17,16 +26,52 @@ async fn main() -> anyhow::Result<()> {
     tracing::info!(%addr, "mangalord listening");
     let listener = tokio::net::TcpListener::bind(addr).await?;
     axum::serve(listener, router)
-        .with_graceful_shutdown(async {
-            let _ = tokio::signal::ctrl_c().await;
-            tracing::info!("ctrl-c received; shutting down");
-        })
+        .with_graceful_shutdown(shutdown_signal())
         .await?;
 
     // Drain background tasks (crawler daemon) before exiting so Chromium
-    // gets a clean shutdown rather than relying on kill-on-drop.
+    // gets a clean shutdown rather than relying on kill-on-drop. Bounded
+    // by a timeout so a wedged shutdown path can't trap the process.
     if let Some(d) = daemon {
-        d.shutdown().await;
+        if tokio::time::timeout(CRAWLER_SHUTDOWN_TIMEOUT, d.shutdown())
+            .await
+            .is_err()
+        {
+            tracing::warn!(
+                timeout_s = CRAWLER_SHUTDOWN_TIMEOUT.as_secs(),
+                "crawler daemon shutdown exceeded timeout; abandoning"
+            );
+        }
     }
     Ok(())
 }
+
+/// Wait for either Ctrl-C (interactive shell) or SIGTERM (Docker /
+/// Kubernetes / Podman / systemd stop) and log which arrived. Without
+/// the SIGTERM branch, `docker compose stop` runs out its grace period
+/// and skips straight to SIGKILL — the daemon never gets the
+/// `daemon.shutdown().await` path, leaking Chromium.
+async fn shutdown_signal() {
+    use tokio::signal::unix::{signal, SignalKind};
+    let mut sigterm = match signal(SignalKind::terminate()) {
+        Ok(s) => s,
+        Err(e) => {
+            // SignalKind::terminate() is supported on every Unix the
+            // tokio runtime runs on; if registration fails we still
+            // honour Ctrl-C so the process is at least
+            // interactive-shutdownable.
+            tracing::warn!(error = %e, "could not install SIGTERM handler; falling back to ctrl_c only");
+            let _ = tokio::signal::ctrl_c().await;
+            tracing::info!("ctrl-c received; shutting down");
+            return;
+        }
+    };
+    tokio::select! {
+        _ = tokio::signal::ctrl_c() => {
+            tracing::info!("ctrl-c received; shutting down");
+        }
+        _ = sigterm.recv() => {
+            tracing::info!("SIGTERM received; shutting down");
+        }
+    }
+}

backend/src/repo/admin_audit.rs

@@ -0,0 +1,32 @@
+//! Admin-action audit log writes.
+//!
+//! Insert is always called from inside the same transaction as the
+//! action it audits — the executor parameter is `PgExecutor` so the
+//! caller passes `&mut *tx` directly.
+
+use sqlx::PgExecutor;
+use uuid::Uuid;
+
+use crate::error::AppResult;
+
+pub async fn insert<'e, E: PgExecutor<'e>>(
+    executor: E,
+    actor_user_id: Uuid,
+    action: &str,
+    target_kind: &str,
+    target_id: Option<Uuid>,
+    payload: serde_json::Value,
+) -> AppResult<()> {
+    sqlx::query(
+        "INSERT INTO admin_audit (actor_user_id, action, target_kind, target_id, payload) \
+         VALUES ($1, $2, $3, $4, $5)",
+    )
+    .bind(actor_user_id)
+    .bind(action)
+    .bind(target_kind)
+    .bind(target_id)
+    .bind(payload)
+    .execute(executor)
+    .await?;
+    Ok(())
+}

backend/src/repo/admin_view.rs

@@ -0,0 +1,232 @@
+//! Admin-facing read queries that join manga/chapter with the crawler
+//! signals (`manga_sources`, `chapter_sources`, `crawler_jobs`) to
+//! derive a sync state per row at query time.
+//!
+//! Priority order for `MangaSyncState`:
+//!   1. `InProgress` — any pending/running `sync_manga` or
+//!      `sync_chapter_list` job matches this manga.
+//!   2. `Dropped` — manga has source rows AND every one of them is
+//!      `dropped_at IS NOT NULL`.
+//!   3. `Synced` — default (includes user-uploaded mangas with no
+//!      `manga_sources` rows at all).
+//!
+//! Priority order for `ChapterSyncState`:
+//!   1. `Downloading` — pending/running `sync_chapter_content` for this id
+//!   2. `Dropped` — chapter has source rows AND all are dropped
+//!   3. `Failed` — `page_count = 0` AND a `dead` `sync_chapter_content`
+//!      row exists for this chapter. Constrained to `page_count = 0`
+//!      because once pages are on disk the chapter IS synced — a
+//!      historical dead job (likely from a re-download attempt that
+//!      crashed) is noise that gets reaped after retention. Surfacing
+//!      "Failed" when content is present would contradict
+//!      `ChapterSyncState::Synced`'s "downloaded at some point" contract.
+//!   4. `NotDownloaded` — `page_count = 0`, no in-flight, no dead job
+//!   5. `Synced` — `page_count > 0`
+//!
+//! Reminder: `done` jobs are reaped after `CRAWLER_JOB_RETENTION_DAYS`,
+//! so `chapters.page_count > 0` is the durable "this is synced" signal,
+//! not the job table.
+
+use chrono::{DateTime, Utc};
+use serde::Serialize;
+use sqlx::{FromRow, PgPool};
+use uuid::Uuid;
+
+use crate::domain::{ChapterSyncState, MangaSyncState};
+use crate::error::AppResult;
+
+#[derive(Debug, Serialize, FromRow)]
+pub struct AdminMangaRow {
+    pub id: Uuid,
+    pub title: String,
+    pub status: String,
+    pub cover_image_path: Option<String>,
+    pub created_at: DateTime<Utc>,
+    pub updated_at: DateTime<Utc>,
+    pub sync_state: MangaSyncState,
+    pub chapter_count: i64,
+    pub latest_seen_at: Option<DateTime<Utc>>,
+}
+
+#[derive(Debug, Default)]
+pub struct ListAdminMangasQuery {
+    pub search: Option<String>,
+    pub sync_state: Option<MangaSyncState>,
+    pub limit: i64,
+    pub offset: i64,
+}
+
+const MANGA_SYNC_STATE_CASE: &str = r#"
+    CASE
+      WHEN EXISTS (
+        SELECT 1 FROM crawler_jobs cj
+         WHERE cj.state IN ('pending','running')
+           AND (
+                (cj.payload->>'kind' = 'sync_chapter_list'
+                 AND (cj.payload->>'manga_id')::uuid = m.id)
+             OR (cj.payload->>'kind' = 'sync_manga'
+                 AND EXISTS (
+                       SELECT 1 FROM manga_sources ms
+                        WHERE ms.manga_id = m.id
+                          AND ms.source_id = cj.payload->>'source_id'
+                          AND ms.source_manga_key = cj.payload->>'source_manga_key'
+                     ))
+              )
+      ) THEN 'in_progress'
+      WHEN EXISTS (SELECT 1 FROM manga_sources ms WHERE ms.manga_id = m.id)
+       AND NOT EXISTS (
+             SELECT 1 FROM manga_sources ms
+              WHERE ms.manga_id = m.id AND ms.dropped_at IS NULL
+           )
+      THEN 'dropped'
+      ELSE 'synced'
+    END
+"#;
+
+/// Paginated admin manga list with derived sync state and total count.
+/// Filters by `search` (substring on title, case-insensitive) and
+/// `sync_state` (post-derivation). The CTE keeps the case expression
+/// in one place — the same projection feeds both the page rows and the
+/// totals count under the same filter.
+pub async fn list_mangas_with_sync_state(
+    pool: &PgPool,
+    q: &ListAdminMangasQuery,
+) -> AppResult<(Vec<AdminMangaRow>, i64)> {
+    let search_pat = q
+        .search
+        .as_ref()
+        .map(|s| format!("%{}%", s.trim()))
+        .filter(|p| p.len() > 2);
+    // sqlx::Type → text: bind the snake_case representation manually so
+    // the SQL can compare it as text without an explicit cast.
+    let sync_filter = q.sync_state.map(|s| match s {
+        MangaSyncState::InProgress => "in_progress",
+        MangaSyncState::Dropped => "dropped",
+        MangaSyncState::Synced => "synced",
+    });
+
+    let sql = format!(
+        r#"
+        WITH classified AS (
+            SELECT
+                m.id, m.title, m.status, m.cover_image_path,
+                m.created_at, m.updated_at,
+                {case} AS sync_state,
+                (SELECT COUNT(*) FROM chapters c WHERE c.manga_id = m.id) AS chapter_count,
+                (SELECT MAX(last_seen_at) FROM manga_sources ms
+                  WHERE ms.manga_id = m.id AND ms.dropped_at IS NULL) AS latest_seen_at
+              FROM mangas m
+             WHERE ($1::text IS NULL OR m.title ILIKE $1)
+        )
+        SELECT * FROM classified
+         WHERE ($2::text IS NULL OR sync_state = $2)
+         ORDER BY updated_at DESC
+         LIMIT $3 OFFSET $4
+        "#,
+        case = MANGA_SYNC_STATE_CASE
+    );
+    let items: Vec<AdminMangaRow> = sqlx::query_as(&sql)
+        .bind(&search_pat)
+        .bind(sync_filter)
+        .bind(q.limit)
+        .bind(q.offset)
+        .fetch_all(pool)
+        .await?;
+
+    let total_sql = format!(
+        r#"
+        WITH classified AS (
+            SELECT {case} AS sync_state
+              FROM mangas m
+             WHERE ($1::text IS NULL OR m.title ILIKE $1)
+        )
+        SELECT COUNT(*) FROM classified
+         WHERE ($2::text IS NULL OR sync_state = $2)
+        "#,
+        case = MANGA_SYNC_STATE_CASE
+    );
+    let total: i64 = sqlx::query_scalar(&total_sql)
+        .bind(&search_pat)
+        .bind(sync_filter)
+        .fetch_one(pool)
+        .await?;
+
+    Ok((items, total))
+}
+
+#[derive(Debug, Serialize, FromRow)]
+pub struct AdminChapterRow {
+    pub id: Uuid,
+    pub manga_id: Uuid,
+    pub number: i32,
+    pub title: Option<String>,
+    pub page_count: i32,
+    pub created_at: DateTime<Utc>,
+    pub sync_state: ChapterSyncState,
+    pub latest_seen_at: Option<DateTime<Utc>>,
+}
+
+#[derive(Debug, Default)]
+pub struct ListAdminChaptersQuery {
+    pub manga_id: Uuid,
+    pub limit: i64,
+    pub offset: i64,
+}
+
+/// Paginated chapter list with derived sync state. Pagination is non-
+/// optional — long-runners can have thousands of chapters and the
+/// per-row scalar subqueries make the unbounded variant a real
+/// stall risk even behind an admin guard. Returns the page slice plus
+/// the unfiltered total so the UI can render "showing N of M".
+pub async fn list_chapters_with_sync_state(
+    pool: &PgPool,
+    q: &ListAdminChaptersQuery,
+) -> AppResult<(Vec<AdminChapterRow>, i64)> {
+    let items: Vec<AdminChapterRow> = sqlx::query_as(
+        r#"
+        SELECT
+            c.id, c.manga_id, c.number, c.title, c.page_count, c.created_at,
+            CASE
+              WHEN EXISTS (
+                SELECT 1 FROM crawler_jobs cj
+                 WHERE cj.state IN ('pending','running')
+                   AND cj.payload->>'kind' = 'sync_chapter_content'
+                   AND (cj.payload->>'chapter_id')::uuid = c.id
+              ) THEN 'downloading'
+              WHEN EXISTS (SELECT 1 FROM chapter_sources cs WHERE cs.chapter_id = c.id)
+               AND NOT EXISTS (
+                     SELECT 1 FROM chapter_sources cs
+                      WHERE cs.chapter_id = c.id AND cs.dropped_at IS NULL
+                   )
+              THEN 'dropped'
+              WHEN c.page_count = 0
+               AND EXISTS (
+                SELECT 1 FROM crawler_jobs cj
+                 WHERE cj.state = 'dead'
+                   AND cj.payload->>'kind' = 'sync_chapter_content'
+                   AND (cj.payload->>'chapter_id')::uuid = c.id
+              ) THEN 'failed'
+              WHEN c.page_count = 0 THEN 'not_downloaded'
+              ELSE 'synced'
+            END AS sync_state,
+            (SELECT MAX(last_seen_at) FROM chapter_sources cs
+              WHERE cs.chapter_id = c.id AND cs.dropped_at IS NULL) AS latest_seen_at
+          FROM chapters c
+         WHERE c.manga_id = $1
+         ORDER BY c.number ASC
+         LIMIT $2 OFFSET $3
+        "#,
+    )
+    .bind(q.manga_id)
+    .bind(q.limit)
+    .bind(q.offset)
+    .fetch_all(pool)
+    .await?;
+
+    let total: i64 = sqlx::query_scalar("SELECT COUNT(*) FROM chapters WHERE manga_id = $1")
+        .bind(q.manga_id)
+        .fetch_one(pool)
+        .await?;
+
+    Ok((items, total))
+}

backend/src/repo/author.rs

@@ -99,6 +99,11 @@ pub async fn list(
 /// Atomically replace the set of authors on a manga. Caller passes a
 /// `&mut PgConnection` (`&mut *tx` works) so the delete+upserts run in
 /// one transaction with whatever called us.
+///
+/// Note: `crawler::repo::sync_authors` does a similar replace with the
+/// same semantics on names. The duplication is intentional — handler
+/// callers want the `Vec<AuthorRef>` for the API response; the
+/// crawler doesn't need it and stays inside its own transaction.
 pub async fn set_for_manga(
     conn: &mut PgConnection,
     manga_id: Uuid,

backend/src/repo/bookmark.rs

@@ -29,9 +29,9 @@ pub async fn create(
 
     match result {
         Ok(b) => Ok(b),
-        Err(e) if is_unique_violation(&e) => Err(AppError::Conflict(
-            "bookmark already exists for this manga/chapter".into(),
-        )),
+        Err(sqlx::Error::Database(ref db_err)) if db_err.is_unique_violation() => Err(
+            AppError::Conflict("bookmark already exists for this manga/chapter".into()),
+        ),
         Err(e) => Err(AppError::Database(e)),
     }
 }
@@ -97,10 +97,3 @@ pub async fn delete(pool: &PgPool, id: Uuid) -> AppResult<()> {
     Ok(())
 }
 
-fn is_unique_violation(err: &sqlx::Error) -> bool {
-    if let sqlx::Error::Database(db_err) = err {
-        db_err.code().as_deref() == Some("23505")
-    } else {
-        false
-    }
-}

backend/src/repo/chapter.rs

@@ -4,7 +4,7 @@ use sqlx::{PgExecutor, PgPool};
 use uuid::Uuid;
 
 use crate::domain::Chapter;
-use crate::error::{AppError, AppResult};
+use crate::error::AppResult;
 
 pub async fn list_for_manga(
     pool: &PgPool,
@@ -12,15 +12,20 @@ pub async fn list_for_manga(
     limit: i64,
     offset: i64,
 ) -> AppResult<Vec<Chapter>> {
-    // Secondary sort by created_at gives duplicate-numbered chapters
-    // (multiple uploaders/translations of the same number) a stable
-    // order in lists and prev/next reader navigation.
+    // Display order = source-site order reversed. The crawler stamps
+    // `source_index` = position in the source DOM (0 = first = newest
+    // on this site, see migration 0021), so DESC puts the oldest
+    // chapter first and keeps the site's variant grouping and the
+    // placement of non-numeric entries (e.g. "notice. : Officials")
+    // intact. NULLS LAST keeps user-uploaded chapters (no source row)
+    // and rows that pre-date the migration below crawled rows; the
+    // (number, created_at) tail then orders them deterministically.
     let rows = sqlx::query_as::<_, Chapter>(
         r#"
         SELECT id, manga_id, number, title, page_count, created_at
         FROM chapters
         WHERE manga_id = $1
-        ORDER BY number ASC, created_at ASC
+        ORDER BY source_index DESC NULLS LAST, number ASC, created_at ASC
         LIMIT $2 OFFSET $3
         "#,
     )
@@ -62,10 +67,9 @@ pub async fn find_by_id_in_manga(
 ///
 /// Chapter identity is the row UUID; the same (manga_id, number)
 /// combination can repeat (multiple translations, re-uploads). The
-/// `is_unique_violation` branch below is a defensive holdover from
-/// 0001's (manga_id, number) UNIQUE — it can no longer fire under
-/// normal operation, but we surface a clean 409 if a future migration
-/// re-adds any chapter uniqueness.
+/// 0013 migration dropped the (manga_id, number) UNIQUE, so duplicate
+/// inserts succeed by design. If a future migration re-adds any
+/// uniqueness, surface a 409 by adding a unique-violation arm here.
 pub async fn create<'e, E: PgExecutor<'e>>(
     executor: E,
     manga_id: Uuid,
@@ -73,7 +77,7 @@ pub async fn create<'e, E: PgExecutor<'e>>(
     title: Option<&str>,
     uploaded_by: Option<Uuid>,
 ) -> AppResult<Chapter> {
-    let result = sqlx::query_as::<_, Chapter>(
+    let row = sqlx::query_as::<_, Chapter>(
         r#"
         INSERT INTO chapters (manga_id, number, title, uploaded_by)
         VALUES ($1, $2, $3, $4)
@@ -85,15 +89,71 @@ pub async fn create<'e, E: PgExecutor<'e>>(
     .bind(title)
     .bind(uploaded_by)
     .fetch_one(executor)
-    .await;
+    .await?;
+    Ok(row)
+}
 
-    match result {
-        Ok(c) => Ok(c),
-        Err(e) if is_unique_violation(&e) => Err(AppError::Conflict(format!(
-            "chapter {number} conflicts with an existing chapter for this manga"
-        ))),
-        Err(e) => Err(AppError::Database(e)),
-    }
+/// Cross-link guard for `POST /bookmarks`: the bookmarks FK accepts
+/// any valid chapter id, but a chapter must belong to the bookmark's
+/// manga or the bookmark would dangle on a foreign manga. Handlers
+/// call this before the insert and surface `NotFound` when it
+/// returns `false`.
+pub async fn belongs_to_manga(
+    pool: &PgPool,
+    chapter_id: Uuid,
+    manga_id: Uuid,
+) -> AppResult<bool> {
+    let (exists,): (bool,) = sqlx::query_as(
+        "SELECT EXISTS(SELECT 1 FROM chapters WHERE id = $1 AND manga_id = $2)",
+    )
+    .bind(chapter_id)
+    .bind(manga_id)
+    .fetch_one(pool)
+    .await?;
+    Ok(exists)
+}
+
+/// Read just the page_count for a chapter. Used by the crawler
+/// daemon's consumer-side dedup safety net so it can ack-done a job
+/// whose chapter has already been fetched by a racing worker.
+pub async fn page_count(pool: &PgPool, id: Uuid) -> sqlx::Result<Option<i32>> {
+    sqlx::query_scalar("SELECT page_count FROM chapters WHERE id = $1")
+        .bind(id)
+        .fetch_optional(pool)
+        .await
+}
+
+/// Look up the manga_id + most recent live source_url for a chapter.
+/// Used by the daemon's chapter dispatcher to resolve the URL it needs
+/// to hand to `content::sync_chapter_content`.
+///
+/// Skips soft-dropped sources (`cs.dropped_at IS NOT NULL`) and breaks
+/// ties between multiple live sources by `last_seen_at DESC`, so the
+/// freshest still-attached URL wins. Returns `None` when the chapter
+/// is gone or all its source rows are dropped — callers in the
+/// dispatcher treat `None` as "ack the job, skip the work."
+///
+/// The enqueue queries (`pipeline::enqueue_bookmarked_pending` and
+/// `enqueue_pending_for_manga`) apply the same `dropped_at IS NULL`
+/// filter — this resolver stays in lockstep so a chapter that was
+/// dropped between enqueue and lease isn't dispatched against a stale
+/// URL.
+pub async fn dispatch_target(
+    pool: &PgPool,
+    chapter_id: Uuid,
+) -> sqlx::Result<Option<(Uuid, String)>> {
+    sqlx::query_as(
+        "SELECT c.manga_id, cs.source_url \
+           FROM chapters c \
+           JOIN chapter_sources cs ON cs.chapter_id = c.id \
+          WHERE c.id = $1 \
+            AND cs.dropped_at IS NULL \
+          ORDER BY cs.last_seen_at DESC \
+          LIMIT 1",
+    )
+    .bind(chapter_id)
+    .fetch_optional(pool)
+    .await
 }
 
 pub async fn set_page_count<'e, E: PgExecutor<'e>>(
@@ -109,10 +169,3 @@ pub async fn set_page_count<'e, E: PgExecutor<'e>>(
     Ok(())
 }
 
-fn is_unique_violation(err: &sqlx::Error) -> bool {
-    if let sqlx::Error::Database(db_err) = err {
-        db_err.code().as_deref() == Some("23505")
-    } else {
-        false
-    }
-}

backend/src/repo/crawler.rs

@@ -8,14 +8,16 @@
 //!   updated (metadata_hash changed), or unchanged.
 //! - [`sync_manga_chapters`]: per-manga chapter reconciliation. Adds
 //!   new ones, refreshes URLs on existing ones, soft-drops vanished.
-//! - [`mark_dropped_mangas`]: end-of-run pass. Any manga from this
-//!   source whose `last_seen_at` is older than the run start is
-//!   soft-dropped.
+//! - [`mark_run_started`] / [`mark_run_completed`] /
+//!   [`last_run_completed_cleanly`]: per-source recovery flag in
+//!   `crawler_state`. A `false` flag on tick start means the previous
+//!   run did not exit cleanly and the next walk should ignore the
+//!   early-stop condition.
 //!
 //! Each public function is a transaction boundary so a partial failure
 //! mid-call leaves the DB in its pre-call state.
 
-use chrono::{DateTime, Utc};
+use chrono::Utc;
 use sqlx::{PgPool, Postgres, Transaction};
 use uuid::Uuid;
 
@@ -274,7 +276,20 @@ async fn sync_tags(
     manga_id: Uuid,
     tags: &[String],
 ) -> sqlx::Result<()> {
-    sqlx::query("DELETE FROM manga_tags WHERE manga_id = $1")
+    // Only clear crawler-owned attachments (added_by IS NULL). User-
+    // attached tags are owned by the attaching user and must survive
+    // the recurring metadata pass — see manga_tags.added_by in
+    // migration 0009.
+    //
+    // Note on orphans: `manga_tags.added_by` is `ON DELETE SET NULL`,
+    // so an attachment whose user was deleted becomes
+    // indistinguishable from a crawler-owned row and is cleaned up
+    // here. That mirrors how `api::mangas::detach_tag` already treats
+    // orphans ("nobody owns it, refuse to let anyone but admin clear
+    // them") — the crawler now becomes the eventual reaper. Tracked
+    // by `sync_tags_garbage_collects_orphan_user_attachments` in
+    // backend/tests/crawler_sync.rs.
+    sqlx::query("DELETE FROM manga_tags WHERE manga_id = $1 AND added_by IS NULL")
         .bind(manga_id)
         .execute(&mut **tx)
         .await?;
@@ -315,18 +330,53 @@ pub async fn sync_manga_chapters(
     chapters: &[SourceChapterRef],
 ) -> sqlx::Result<ChapterDiff> {
     let mut tx = pool.begin().await?;
+    // Per-manga advisory lock. Two concurrent calls for the same manga
+    // would otherwise both read `seen_keys`, both run the drop UPDATE
+    // filtered on `NOT (key = ANY $3)`, and the later commit could soft-
+    // drop a chapter the earlier commit had just inserted (lost-update
+    // shape under MVCC). `pg_advisory_xact_lock` is scoped to this
+    // transaction: it auto-releases on COMMIT/ROLLBACK so a Rust-side
+    // panic mid-call doesn't strand the lock. The single-arg int8 form
+    // keyed by `hashtextextended(manga_id::text, 0)` shares Postgres'
+    // global advisory-lock namespace with `CRON_LOCK_KEY`, but collision
+    // is 2^-64 per pair (a UUID-derived hash hitting the fixed cron key
+    // is effectively impossible).
+    sqlx::query("SELECT pg_advisory_xact_lock(hashtextextended($1::text, 0))")
+        .bind(manga_id)
+        .execute(&mut *tx)
+        .await?;
+
     let mut diff = ChapterDiff::default();
     let seen_keys: Vec<String> = chapters
         .iter()
         .map(|c| c.source_chapter_key.clone())
         .collect();
 
-    for c in chapters {
+    for (idx, c) in chapters.iter().enumerate() {
+        // `source_index` captures the chapter's position in the source
+        // DOM (0 = first = newest on this site) so the list query can
+        // reverse it for the user-facing list — see migration 0021.
+        // Every sync overwrites the value on both branches, so a new
+        // chapter inserted at the top of the source shifts every other
+        // row down by one on the next tick.
+        let source_index = idx as i32;
+        // Lookup is constrained by manga_id (via the chapters join) so a
+        // source whose chapter slugs collide across mangas (e.g.
+        // "chapter-1" appearing under two different mangas) attributes
+        // each row to the correct manga. Migration 0017 dropped the
+        // (source_id, source_chapter_key) PK in favour of
+        // (source_id, chapter_id) for exactly this reason.
         let existing: Option<(Uuid,)> = sqlx::query_as(
-            "SELECT chapter_id FROM chapter_sources WHERE source_id = $1 AND source_chapter_key = $2",
+            "SELECT cs.chapter_id \
+               FROM chapter_sources cs \
+               JOIN chapters ch ON ch.id = cs.chapter_id \
+              WHERE cs.source_id = $1 \
+                AND cs.source_chapter_key = $2 \
+                AND ch.manga_id = $3",
         )
         .bind(source_id)
         .bind(&c.source_chapter_key)
+        .bind(manga_id)
         .fetch_optional(&mut *tx)
         .await?;
 
@@ -339,14 +389,15 @@ pub async fn sync_manga_chapters(
                 // identity is the UUID, not the number.
                 let (chapter_id,): (Uuid,) = sqlx::query_as(
                     r#"
-                    INSERT INTO chapters (manga_id, number, title, page_count)
-                    VALUES ($1, $2, $3, 0)
+                    INSERT INTO chapters (manga_id, number, title, page_count, source_index)
+                    VALUES ($1, $2, $3, 0, $4)
                     RETURNING id
                     "#,
                 )
                 .bind(manga_id)
                 .bind(c.number)
                 .bind(c.title.as_deref())
+                .bind(source_index)
                 .fetch_one(&mut *tx)
                 .await?;
                 sqlx::query(
@@ -365,21 +416,27 @@ pub async fn sync_manga_chapters(
                 diff.new += 1;
             }
             Some((chapter_id,)) => {
-                sqlx::query("UPDATE chapters SET title = $1 WHERE id = $2")
+                sqlx::query(
+                    "UPDATE chapters SET title = $1, source_index = $2 WHERE id = $3",
+                )
                     .bind(c.title.as_deref())
+                    .bind(source_index)
                     .bind(chapter_id)
                     .execute(&mut *tx)
                     .await?;
+                // chapter_id is now the natural per-(source, chapter)
+                // identifier — use it directly instead of re-keying on
+                // (source_id, source_chapter_key) which may not be unique.
                 sqlx::query(
                     r#"
                     UPDATE chapter_sources
                        SET source_url = $1, last_seen_at = NOW(), dropped_at = NULL
-                     WHERE source_id = $2 AND source_chapter_key = $3
+                     WHERE source_id = $2 AND chapter_id = $3
                     "#,
                 )
                 .bind(&c.url)
                 .bind(source_id)
-                .bind(&c.source_chapter_key)
+                .bind(chapter_id)
                 .execute(&mut *tx)
                 .await?;
                 diff.refreshed += 1;
@@ -412,19 +469,52 @@ pub async fn sync_manga_chapters(
     Ok(diff)
 }
 
-/// Record that a complete Backfill walk has finished for `source_id`.
-/// The presence of this row is what the daemon's mode auto-detection
-/// uses to flip from Backfill to Incremental on subsequent ticks.
+/// Count the chapters that the source `(source_id, source_manga_key)`
+/// is currently known to attach to — i.e. the number of `chapter_sources`
+/// rows for the manga identified by the (source_id, source_manga_key)
+/// pair, restricted to live (`dropped_at IS NULL`) rows.
 ///
-/// Keyed `seed_completed:<source_id>` in `crawler_state`. JSON payload
-/// stores the timestamp so we can surface "last fully reseeded at" in
-/// future ops tooling without another migration.
-pub async fn mark_seed_completed(
+/// Used by the metadata pass's partial-render guard: if `fetch_manga`
+/// returns an empty `chapters` Vec but the source previously surfaced
+/// chapters here, that's most likely a chromium snapshot taken between
+/// the `#chapter_table` wrapper render and its rows render — the
+/// safest move is to skip `sync_manga_chapters` so the soft-drop
+/// branch doesn't flip every existing chapter to `dropped_at`.
+///
+/// Returns `Ok(0)` when the manga is brand-new (no `manga_sources`
+/// row yet), which is the legitimate "this manga has no chapters yet"
+/// case and must NOT be flagged.
+pub async fn live_chapter_count_for_source_manga(
     pool: &PgPool,
     source_id: &str,
-    at: DateTime<Utc>,
-) -> sqlx::Result<()> {
-    let key = format!("seed_completed:{source_id}");
+    source_manga_key: &str,
+) -> sqlx::Result<i64> {
+    let row: Option<(i64,)> = sqlx::query_as(
+        "SELECT COUNT(*) \
+           FROM chapter_sources cs \
+           JOIN chapters c ON c.id = cs.chapter_id \
+           JOIN manga_sources ms \
+             ON ms.manga_id = c.manga_id \
+            AND ms.source_id = cs.source_id \
+          WHERE ms.source_id = $1 \
+            AND ms.source_manga_key = $2 \
+            AND cs.dropped_at IS NULL",
+    )
+    .bind(source_id)
+    .bind(source_manga_key)
+    .fetch_optional(pool)
+    .await?;
+    Ok(row.map(|(n,)| n).unwrap_or(0))
+}
+
+/// Mark a metadata pass as in-flight for `source_id`. Stamps
+/// `last_run_completed:<source_id>` in `crawler_state` with
+/// `{"completed": false, "at": now}`. A crash, panic, or SIGKILL after
+/// this point leaves the flag at `false`, which the next tick reads as
+/// "previous run did not exit cleanly — walk the full catalog this
+/// time" (recovery sweep).
+pub async fn mark_run_started(pool: &PgPool, source_id: &str) -> sqlx::Result<()> {
+    let key = format!("last_run_completed:{source_id}");
     sqlx::query(
         "INSERT INTO crawler_state (key, value, updated_at) \
          VALUES ($1, $2, now()) \
@@ -432,50 +522,99 @@ pub async fn mark_seed_completed(
             SET value = EXCLUDED.value, updated_at = now()",
     )
     .bind(&key)
-    .bind(serde_json::json!({ "at": at.to_rfc3339() }))
+    .bind(serde_json::json!({
+        "completed": false,
+        "at": Utc::now().to_rfc3339(),
+    }))
     .execute(pool)
     .await?;
     Ok(())
 }
 
-/// Read the timestamp written by [`mark_seed_completed`], if any.
-/// `None` means no complete Backfill has ever finished for this
-/// source — the daemon should run Backfill on the next tick.
-pub async fn seed_completed_at(
+/// Mark a metadata pass as completed cleanly for `source_id`. Called
+/// from the same place a run decides it reached end-of-walk or hit the
+/// intentional stop. The next tick reads `true` and applies the normal
+/// stop condition.
+pub async fn mark_run_completed(pool: &PgPool, source_id: &str) -> sqlx::Result<()> {
+    let key = format!("last_run_completed:{source_id}");
+    sqlx::query(
+        "INSERT INTO crawler_state (key, value, updated_at) \
+         VALUES ($1, $2, now()) \
+         ON CONFLICT (key) DO UPDATE \
+            SET value = EXCLUDED.value, updated_at = now()",
+    )
+    .bind(&key)
+    .bind(serde_json::json!({
+        "completed": true,
+        "at": Utc::now().to_rfc3339(),
+    }))
+    .execute(pool)
+    .await?;
+    Ok(())
+}
+
+/// List mangas whose `cover_image_path IS NULL` but a live
+/// `manga_sources` row still attaches them to a source. The bounded
+/// result feeds the cover-backfill pass in [`crate::crawler::pipeline`]:
+/// each entry is one (manga, freshest source row) pair where a cover
+/// re-download is in order.
+///
+/// Per-manga deduplication uses `DISTINCT ON (m.id)` keyed on the row
+/// with the newest `last_seen_at`, so a manga that's surfaced by
+/// multiple sources only produces one row (the freshest). Sort is
+/// stable for tests.
+pub async fn list_missing_covers(
+    pool: &PgPool,
+    max: i64,
+) -> sqlx::Result<Vec<MissingCoverEntry>> {
+    let rows: Vec<(Uuid, String, String)> = sqlx::query_as(
+        r#"
+        SELECT DISTINCT ON (m.id) m.id, ms.source_manga_key, ms.source_url
+          FROM mangas m
+          JOIN manga_sources ms ON ms.manga_id = m.id
+         WHERE m.cover_image_path IS NULL
+           AND ms.dropped_at IS NULL
+         ORDER BY m.id, ms.last_seen_at DESC
+         LIMIT $1
+        "#,
+    )
+    .bind(max)
+    .fetch_all(pool)
+    .await?;
+    Ok(rows
+        .into_iter()
+        .map(|(manga_id, source_manga_key, source_url)| MissingCoverEntry {
+            manga_id,
+            source_manga_key,
+            source_url,
+        })
+        .collect())
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct MissingCoverEntry {
+    pub manga_id: Uuid,
+    pub source_manga_key: String,
+    pub source_url: String,
+}
+
+/// Read the recovery flag for `source_id`. A missing row OR an
+/// unparseable value reads as `true` ("clean") — the former covers the
+/// first-ever run on a virgin DB (no recovery needed), the latter
+/// covers forward-compat against future schema changes; both fail-safe
+/// toward not making an operator pay for an unnecessary full sweep.
+pub async fn last_run_completed_cleanly(
     pool: &PgPool,
     source_id: &str,
-) -> sqlx::Result<Option<DateTime<Utc>>> {
-    let key = format!("seed_completed:{source_id}");
+) -> sqlx::Result<bool> {
+    let key = format!("last_run_completed:{source_id}");
     let row: Option<serde_json::Value> =
         sqlx::query_scalar("SELECT value FROM crawler_state WHERE key = $1")
             .bind(&key)
             .fetch_optional(pool)
             .await?;
-    Ok(row.and_then(|v| {
-        v.get("at")
-            .and_then(|s| s.as_str())
-            .and_then(|s| DateTime::parse_from_rfc3339(s).ok())
-            .map(|dt| dt.with_timezone(&Utc))
-    }))
+    Ok(row
+        .and_then(|v| v.get("completed").and_then(|b| b.as_bool()))
+        .unwrap_or(true))
 }
 
-pub async fn mark_dropped_mangas(
-    pool: &PgPool,
-    source_id: &str,
-    run_started_at: DateTime<Utc>,
-) -> sqlx::Result<u64> {
-    let res = sqlx::query(
-        r#"
-        UPDATE manga_sources
-           SET dropped_at = NOW()
-         WHERE source_id = $1
-           AND last_seen_at < $2
-           AND dropped_at IS NULL
-        "#,
-    )
-    .bind(source_id)
-    .bind(run_started_at)
-    .execute(pool)
-    .await?;
-    Ok(res.rows_affected())
-}

backend/src/repo/genre.rs

@@ -61,6 +61,11 @@ pub async fn load_for_mangas(
 /// FK constraint would reject them, so we filter upstream rather than
 /// surface a 500 here. (The API layer validates the set against
 /// `list_all` first.)
+///
+/// Note: `crawler::repo::sync_genres` does a similar replace, but by
+/// *name* and with auto-create of unseen genres — the crawler can't
+/// validate against the curated vocabulary on its own. Both paths are
+/// intentional; don't merge them without preserving that semantic.
 pub async fn set_for_manga(
     conn: &mut PgConnection,
     manga_id: Uuid,

backend/src/repo/manga.rs

@@ -281,3 +281,17 @@ pub async fn exists(pool: &PgPool, id: Uuid) -> AppResult<bool> {
             .await?;
     Ok(exists)
 }
+
+/// Returns the uploader's user id for a manga. `None` either when the
+/// manga doesn't exist or when the row predates the `uploaded_by`
+/// column (historical NULL — see migration 0011). Callers must
+/// distinguish "manga missing" via [`exists`] before relying on this
+/// to make an authz decision.
+pub async fn uploaded_by(pool: &PgPool, id: Uuid) -> AppResult<Option<Uuid>> {
+    let row: Option<(Option<Uuid>,)> =
+        sqlx::query_as("SELECT uploaded_by FROM mangas WHERE id = $1")
+            .bind(id)
+            .fetch_optional(pool)
+            .await?;
+    Ok(row.and_then(|(u,)| u))
+}

backend/src/repo/mod.rs

@@ -1,3 +1,5 @@
+pub mod admin_audit;
+pub mod admin_view;
 pub mod api_token;
 pub mod author;
 pub mod bookmark;

backend/src/repo/user.rs

@@ -11,7 +11,7 @@ pub async fn create(pool: &PgPool, username: &str, password_hash: &str) -> AppRe
         r#"
         INSERT INTO users (username, password_hash)
         VALUES ($1, $2)
-        RETURNING id, username, password_hash, created_at
+        RETURNING id, username, password_hash, created_at, is_admin
         "#,
     )
     .bind(username)
@@ -21,7 +21,7 @@ pub async fn create(pool: &PgPool, username: &str, password_hash: &str) -> AppRe
 
     match result {
         Ok(user) => Ok(user),
-        Err(e) if is_unique_violation(&e) => {
+        Err(sqlx::Error::Database(ref db_err)) if db_err.is_unique_violation() => {
             Err(AppError::Conflict("username is already taken".into()))
         }
         Err(e) => Err(AppError::Database(e)),
@@ -35,7 +35,7 @@ pub async fn create(pool: &PgPool, username: &str, password_hash: &str) -> AppRe
 pub async fn find_by_username(pool: &PgPool, username: &str) -> AppResult<Option<User>> {
     let row = sqlx::query_as::<_, User>(
         r#"
-        SELECT id, username, password_hash, created_at
+        SELECT id, username, password_hash, created_at, is_admin
         FROM users
         WHERE lower(username) = lower($1)
         "#,
@@ -48,7 +48,7 @@ pub async fn find_by_username(pool: &PgPool, username: &str) -> AppResult<Option
 
 pub async fn find_by_id(pool: &PgPool, id: Uuid) -> AppResult<Option<User>> {
     let row = sqlx::query_as::<_, User>(
-        r#"SELECT id, username, password_hash, created_at FROM users WHERE id = $1"#,
+        r#"SELECT id, username, password_hash, created_at, is_admin FROM users WHERE id = $1"#,
     )
     .bind(id)
     .fetch_optional(pool)
@@ -56,10 +56,317 @@ pub async fn find_by_id(pool: &PgPool, id: Uuid) -> AppResult<Option<User>> {
     Ok(row)
 }
 
-fn is_unique_violation(err: &sqlx::Error) -> bool {
-    if let sqlx::Error::Database(db_err) = err {
-        db_err.code().as_deref() == Some("23505")
-    } else {
-        false
-    }
+/// Postgres advisory-lock key guarding admin-count-changing operations
+/// (demote, delete-admin). Without this lock two concurrent demotes of
+/// different admins could each pass their "more than one admin remains"
+/// check, then commit, leaving zero admins. The lock serialises any tx
+/// that might change the admin count so the recount under the lock is
+/// authoritative.
+///
+/// Value is the bytes of "admininv" interpreted as a big-endian i64.
+/// Postgres' advisory-lock keyspace is global; collision risk with
+/// `CRON_LOCK_KEY` and friends is ~2^-64.
+pub const ADMIN_INVARIANT_LOCK_KEY: i64 = 0x61_64_6d_69_6e_69_6e_76;
+
+#[derive(Debug, Default)]
+pub struct ListUsersQuery {
+    pub search: Option<String>,
+    pub limit: i64,
+    pub offset: i64,
+}
+
+/// Paginated user list with total count. `search` is a case-insensitive
+/// substring match on `username`. Order is alphabetical by username so
+/// pagination is stable across concurrent writes (mangas changing
+/// is_admin doesn't reshuffle the page).
+pub async fn list_with_total(
+    pool: &PgPool,
+    q: &ListUsersQuery,
+) -> AppResult<(Vec<User>, i64)> {
+    let pat = q
+        .search
+        .as_ref()
+        .map(|s| format!("%{}%", s.trim()))
+        .filter(|p| p.len() > 2);
+
+    let items = sqlx::query_as::<_, User>(
+        r#"
+        SELECT id, username, password_hash, created_at, is_admin
+          FROM users
+         WHERE ($1::text IS NULL OR username ILIKE $1)
+         ORDER BY username
+         LIMIT $2 OFFSET $3
+        "#,
+    )
+    .bind(&pat)
+    .bind(q.limit)
+    .bind(q.offset)
+    .fetch_all(pool)
+    .await?;
+
+    let total: i64 = sqlx::query_scalar(
+        "SELECT COUNT(*) FROM users WHERE ($1::text IS NULL OR username ILIKE $1)",
+    )
+    .bind(&pat)
+    .fetch_one(pool)
+    .await?;
+
+    Ok((items, total))
+}
+
+/// Raw `is_admin` update with no safety checks, no audit log, and no
+/// advisory lock. Exists only as a test setup helper for the admin-
+/// feature integration suite — production code MUST go through
+/// [`admin_safe_set_is_admin`], which enforces self-protection, the
+/// last-admin invariant, and the audit log atomically.
+pub async fn set_is_admin_unchecked(pool: &PgPool, id: Uuid, value: bool) -> AppResult<()> {
+    sqlx::query("UPDATE users SET is_admin = $1 WHERE id = $2")
+        .bind(value)
+        .bind(id)
+        .execute(pool)
+        .await?;
+    Ok(())
+}
+
+/// Ensure the user `username` exists and is an admin. Called at startup
+/// from `app::build` when `ADMIN_USERNAME` / `ADMIN_PASSWORD` are set.
+///
+/// Semantics — see cross-cutting decision #2 in the feature plan:
+/// - If no row exists: create with the env-supplied password hashed via
+///   argon2id and `is_admin = true`.
+/// - If a row already exists: flip `is_admin` to true if needed; **never**
+///   touch the existing `password_hash`. Lets the operator rotate the
+///   admin password through the UI without env-var conflict.
+/// Wrapped in a transaction so a concurrent `register` for the same
+/// username can't slip an INSERT between the SELECT and UPDATE/INSERT.
+/// Set `is_admin` on a user with full safety checks: rejects self-demote,
+/// rejects demoting the only remaining admin (under `ADMIN_INVARIANT_LOCK_KEY`
+/// to close the parallel-demote race), and writes an `admin_audit` row
+/// in the same tx so the log mirrors what actually committed.
+///
+/// Returns the freshly-written user row (so the handler can return it
+/// without a second SELECT).
+pub async fn admin_safe_set_is_admin(
+    pool: &PgPool,
+    actor_id: Uuid,
+    target_id: Uuid,
+    value: bool,
+) -> AppResult<User> {
+    // Cheap pre-check before opening a tx — also covers the "demote me"
+    // case which would otherwise pass the recount when other admins exist.
+    if actor_id == target_id && !value {
+        return Err(AppError::Conflict(
+            "cannot demote yourself; ask another admin".into(),
+        ));
+    }
+
+    let mut tx = pool.begin().await?;
+    sqlx::query("SELECT pg_advisory_xact_lock($1)")
+        .bind(ADMIN_INVARIANT_LOCK_KEY)
+        .execute(&mut *tx)
+        .await?;
+
+    let target: Option<User> = sqlx::query_as(
+        "SELECT id, username, password_hash, created_at, is_admin \
+           FROM users WHERE id = $1 FOR UPDATE",
+    )
+    .bind(target_id)
+    .fetch_optional(&mut *tx)
+    .await?;
+    let Some(target) = target else {
+        return Err(AppError::NotFound);
+    };
+
+    // No-op: caller asked to set `is_admin` to its current value. Return
+    // the row as-is without writing an audit entry — otherwise repeated
+    // PATCH calls (browser retry, double-click) pile misleading
+    // "promote_user" rows in `admin_audit` for actions that changed
+    // nothing.
+    if target.is_admin == value {
+        tx.commit().await?;
+        return Ok(target);
+    }
+
+    // Recount inside the lock — this is the authoritative read.
+    if target.is_admin && !value {
+        let admin_count: i64 =
+            sqlx::query_scalar("SELECT COUNT(*) FROM users WHERE is_admin = true")
+                .fetch_one(&mut *tx)
+                .await?;
+        if admin_count <= 1 {
+            return Err(AppError::Conflict(
+                "cannot demote the last admin; promote another user first".into(),
+            ));
+        }
+    }
+
+    let updated: User = sqlx::query_as(
+        "UPDATE users SET is_admin = $1 WHERE id = $2 \
+         RETURNING id, username, password_hash, created_at, is_admin",
+    )
+    .bind(value)
+    .bind(target_id)
+    .fetch_one(&mut *tx)
+    .await?;
+
+    let action = if value { "promote_user" } else { "demote_user" };
+    crate::repo::admin_audit::insert(
+        &mut *tx,
+        actor_id,
+        action,
+        "user",
+        Some(target_id),
+        serde_json::json!({ "username": target.username }),
+    )
+    .await?;
+
+    tx.commit().await?;
+    Ok(updated)
+}
+
+/// Delete a user with full safety checks: rejects self-delete, rejects
+/// deleting the only remaining admin (under `ADMIN_INVARIANT_LOCK_KEY`),
+/// and writes an `admin_audit` row in the same tx. Captures the deleted
+/// username + admin status in the audit payload so the action is
+/// readable after the user row itself is gone.
+pub async fn admin_safe_delete(
+    pool: &PgPool,
+    actor_id: Uuid,
+    target_id: Uuid,
+) -> AppResult<()> {
+    if actor_id == target_id {
+        return Err(AppError::Conflict(
+            "cannot delete yourself; ask another admin".into(),
+        ));
+    }
+
+    let mut tx = pool.begin().await?;
+    sqlx::query("SELECT pg_advisory_xact_lock($1)")
+        .bind(ADMIN_INVARIANT_LOCK_KEY)
+        .execute(&mut *tx)
+        .await?;
+
+    let target: Option<User> = sqlx::query_as(
+        "SELECT id, username, password_hash, created_at, is_admin \
+           FROM users WHERE id = $1 FOR UPDATE",
+    )
+    .bind(target_id)
+    .fetch_optional(&mut *tx)
+    .await?;
+    let Some(target) = target else {
+        return Err(AppError::NotFound);
+    };
+
+    if target.is_admin {
+        let admin_count: i64 =
+            sqlx::query_scalar("SELECT COUNT(*) FROM users WHERE is_admin = true")
+                .fetch_one(&mut *tx)
+                .await?;
+        if admin_count <= 1 {
+            return Err(AppError::Conflict(
+                "cannot delete the last admin; promote another user first".into(),
+            ));
+        }
+    }
+
+    sqlx::query("DELETE FROM users WHERE id = $1")
+        .bind(target_id)
+        .execute(&mut *tx)
+        .await?;
+
+    crate::repo::admin_audit::insert(
+        &mut *tx,
+        actor_id,
+        "delete_user",
+        "user",
+        Some(target_id),
+        serde_json::json!({
+            "username": target.username,
+            "was_admin": target.is_admin,
+        }),
+    )
+    .await?;
+
+    tx.commit().await?;
+    Ok(())
+}
+
+/// Admin-initiated user creation. Wraps the INSERT + audit row in a
+/// single transaction so a rolled-back create never leaves an orphan
+/// audit entry. Caller (HTTP handler) is responsible for validating
+/// `username`/`password` and hashing — this fn assumes both are
+/// already vetted by the same `validate_*` rules used by self-
+/// registration.
+pub async fn admin_create_user(
+    pool: &PgPool,
+    actor_id: Uuid,
+    username: &str,
+    password_hash: &str,
+    is_admin: bool,
+) -> AppResult<User> {
+    let mut tx = pool.begin().await?;
+    let user: User = match sqlx::query_as::<_, User>(
+        "INSERT INTO users (username, password_hash, is_admin) VALUES ($1, $2, $3) \
+         RETURNING id, username, password_hash, created_at, is_admin",
+    )
+    .bind(username)
+    .bind(password_hash)
+    .bind(is_admin)
+    .fetch_one(&mut *tx)
+    .await
+    {
+        Ok(u) => u,
+        Err(sqlx::Error::Database(ref db_err)) if db_err.is_unique_violation() => {
+            return Err(AppError::Conflict("username is already taken".into()));
+        }
+        Err(e) => return Err(AppError::Database(e)),
+    };
+
+    crate::repo::admin_audit::insert(
+        &mut *tx,
+        actor_id,
+        "create_user",
+        "user",
+        Some(user.id),
+        serde_json::json!({
+            "username": user.username,
+            "is_admin": user.is_admin,
+        }),
+    )
+    .await?;
+
+    tx.commit().await?;
+    Ok(user)
+}
+
+pub async fn bootstrap_admin(
+    pool: &PgPool,
+    username: &str,
+    password: &str,
+) -> AppResult<()> {
+    let mut tx = pool.begin().await?;
+    let existing: Option<(Uuid,)> = sqlx::query_as(
+        "SELECT id FROM users WHERE lower(username) = lower($1) FOR UPDATE",
+    )
+    .bind(username)
+    .fetch_optional(&mut *tx)
+    .await?;
+    match existing {
+        Some((id,)) => {
+            sqlx::query("UPDATE users SET is_admin = true WHERE id = $1 AND is_admin = false")
+                .bind(id)
+                .execute(&mut *tx)
+                .await?;
+        }
+        None => {
+            let hash = crate::auth::password::hash_password(password)?;
+            sqlx::query("INSERT INTO users (username, password_hash, is_admin) VALUES ($1, $2, true)")
+                .bind(username)
+                .bind(&hash)
+                .execute(&mut *tx)
+                .await?;
+        }
+    }
+    tx.commit().await?;
+    Ok(())
 }

backend/src/storage/local.rs

@@ -16,6 +16,13 @@ impl LocalStorage {
     }
 
     fn resolve(&self, key: &str) -> Result<PathBuf, StorageError> {
+        // NUL bytes are rejected by the Linux syscall layer, but the
+        // error surfaces as an opaque IO failure rather than the
+        // explicit `BadKey` the rest of the contract uses. Catch it
+        // here so the error path is consistent.
+        if key.contains('\0') {
+            return Err(StorageError::BadKey);
+        }
         let key = key.trim_start_matches('/');
         if key.is_empty() {
             return Err(StorageError::BadKey);
@@ -79,6 +86,10 @@ impl Storage for LocalStorage {
         let path: &Path = &self.resolve(key)?;
         Ok(fs::try_exists(path).await?)
     }
+
+    fn local_root(&self) -> Option<&Path> {
+        Some(&self.root)
+    }
 }
 
 #[cfg(test)]
@@ -114,6 +125,9 @@ mod tests {
         assert!(matches!(s.get(".").await, Err(StorageError::BadKey)));
         // Empty segment via doubled slash.
         assert!(matches!(s.get("a//b").await, Err(StorageError::BadKey)));
+        // NUL byte (rejected explicitly so callers see BadKey rather
+        // than an opaque IO error from the kernel).
+        assert!(matches!(s.put("a\0b", b"x").await, Err(StorageError::BadKey)));
     }
 
     #[tokio::test]

backend/src/storage/mod.rs

@@ -9,6 +9,8 @@ mod local;
 use std::io;
 use std::pin::Pin;
 
+use std::path::Path;
+
 use async_trait::async_trait;
 use bytes::Bytes;
 use futures_core::Stream;
@@ -44,4 +46,13 @@ pub trait Storage: Send + Sync {
     async fn get_stream(&self, key: &str) -> Result<StreamingFile, StorageError>;
     async fn delete(&self, key: &str) -> Result<(), StorageError>;
     async fn exists(&self, key: &str) -> Result<bool, StorageError>;
+
+    /// Filesystem path the backend is rooted at, when introspectable.
+    /// Returns `None` for backends that aren't a local filesystem (e.g.
+    /// a future `S3Storage`). The admin system endpoint uses this to
+    /// statvfs the data dir; backends that return `None` get a `disk:
+    /// null` payload instead of fabricated numbers.
+    fn local_root(&self) -> Option<&Path> {
+        None
+    }
 }

backend/tests/api_admin_mangas.rs

@@ -0,0 +1,548 @@
+//! PR 3 (feat/admin-mangas-api) integration tests.
+//!
+//! Per-variant fixture tests for the derived sync-state SQL plus
+//! happy-path E2E for the two admin endpoints. Auth-gate regression
+//! (403/401) is covered by PR 1's `RequireAdmin` test matrix; the only
+//! gate test here is one spot check per endpoint.
+
+mod common;
+
+use axum::http::StatusCode;
+use axum::Router;
+use serde_json::json;
+use sqlx::PgPool;
+use tower::ServiceExt;
+use uuid::Uuid;
+
+use mangalord::repo;
+
+const SOURCE_ID: &str = "test-source";
+
+async fn seed_admin(pool: &PgPool, app: &Router) -> (String, String) {
+    let (username, cookie) = common::register_user(app).await;
+    let u = repo::user::find_by_username(pool, &username)
+        .await
+        .unwrap()
+        .unwrap();
+    repo::user::set_is_admin_unchecked(pool, u.id, true).await.unwrap();
+    (username, cookie)
+}
+
+async fn seed_source(pool: &PgPool) {
+    repo::crawler::ensure_source(pool, SOURCE_ID, "Test", "https://example.test")
+        .await
+        .unwrap();
+}
+
+async fn insert_manga(pool: &PgPool, title: &str) -> Uuid {
+    let (id,): (Uuid,) = sqlx::query_as(
+        "INSERT INTO mangas (title, status, alt_titles) VALUES ($1, 'ongoing', ARRAY[]::text[]) RETURNING id",
+    )
+    .bind(title)
+    .fetch_one(pool)
+    .await
+    .unwrap();
+    id
+}
+
+async fn insert_manga_source(
+    pool: &PgPool,
+    manga_id: Uuid,
+    source_manga_key: &str,
+    dropped: bool,
+) {
+    let dropped_at = if dropped { "now()" } else { "NULL" };
+    let sql = format!(
+        "INSERT INTO manga_sources (source_id, source_manga_key, manga_id, source_url, dropped_at) \
+         VALUES ($1, $2, $3, 'https://example.test/m', {dropped_at})"
+    );
+    sqlx::query(&sql)
+        .bind(SOURCE_ID)
+        .bind(source_manga_key)
+        .bind(manga_id)
+        .execute(pool)
+        .await
+        .unwrap();
+}
+
+async fn insert_chapter(pool: &PgPool, manga_id: Uuid, number: i32, page_count: i32) -> Uuid {
+    let (id,): (Uuid,) = sqlx::query_as(
+        "INSERT INTO chapters (manga_id, number, title, page_count) VALUES ($1, $2, NULL, $3) RETURNING id",
+    )
+    .bind(manga_id)
+    .bind(number)
+    .bind(page_count)
+    .fetch_one(pool)
+    .await
+    .unwrap();
+    id
+}
+
+async fn insert_chapter_source(
+    pool: &PgPool,
+    chapter_id: Uuid,
+    source_chapter_key: &str,
+    dropped: bool,
+) {
+    let dropped_at = if dropped { "now()" } else { "NULL" };
+    let sql = format!(
+        "INSERT INTO chapter_sources (source_id, source_chapter_key, chapter_id, source_url, dropped_at) \
+         VALUES ($1, $2, $3, 'https://example.test/c', {dropped_at})"
+    );
+    sqlx::query(&sql)
+        .bind(SOURCE_ID)
+        .bind(source_chapter_key)
+        .bind(chapter_id)
+        .execute(pool)
+        .await
+        .unwrap();
+}
+
+async fn insert_job(pool: &PgPool, payload: serde_json::Value, state: &str) {
+    sqlx::query("INSERT INTO crawler_jobs (payload, state) VALUES ($1, $2)")
+        .bind(payload)
+        .bind(state)
+        .execute(pool)
+        .await
+        .unwrap();
+}
+
+/// Per-variant tests don't care about pagination — fetch the whole
+/// chapter set (up to the hard cap) and discard the total.
+async fn fetch_chapter_rows(
+    pool: &PgPool,
+    manga_id: Uuid,
+) -> Vec<mangalord::repo::admin_view::AdminChapterRow> {
+    let (rows, _) = repo::admin_view::list_chapters_with_sync_state(
+        pool,
+        &repo::admin_view::ListAdminChaptersQuery {
+            manga_id,
+            limit: 500,
+            offset: 0,
+        },
+    )
+    .await
+    .unwrap();
+    rows
+}
+
+// ---- manga sync state ------------------------------------------------------
+
+#[sqlx::test(migrations = "./migrations")]
+async fn manga_state_synced_for_fresh_source(pool: PgPool) {
+    seed_source(&pool).await;
+    let m = insert_manga(&pool, "Synced Manga").await;
+    insert_manga_source(&pool, m, "smk-1", false).await;
+
+    let (rows, total) = repo::admin_view::list_mangas_with_sync_state(
+        &pool,
+        &repo::admin_view::ListAdminMangasQuery {
+            limit: 50,
+            ..Default::default()
+        },
+    )
+    .await
+    .unwrap();
+    assert_eq!(total, 1);
+    assert_eq!(rows[0].id, m);
+    assert_eq!(rows[0].sync_state, mangalord::domain::MangaSyncState::Synced);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn manga_state_synced_for_user_upload_without_sources(pool: PgPool) {
+    let m = insert_manga(&pool, "User Upload").await;
+    let (rows, _) = repo::admin_view::list_mangas_with_sync_state(
+        &pool,
+        &repo::admin_view::ListAdminMangasQuery {
+            limit: 50,
+            ..Default::default()
+        },
+    )
+    .await
+    .unwrap();
+    assert_eq!(rows[0].id, m);
+    assert_eq!(rows[0].sync_state, mangalord::domain::MangaSyncState::Synced);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn manga_state_dropped_when_all_sources_dropped(pool: PgPool) {
+    seed_source(&pool).await;
+    let m = insert_manga(&pool, "Dropped Manga").await;
+    insert_manga_source(&pool, m, "smk-1", true).await;
+
+    let (rows, _) = repo::admin_view::list_mangas_with_sync_state(
+        &pool,
+        &repo::admin_view::ListAdminMangasQuery {
+            limit: 50,
+            ..Default::default()
+        },
+    )
+    .await
+    .unwrap();
+    assert_eq!(rows[0].id, m);
+    assert_eq!(rows[0].sync_state, mangalord::domain::MangaSyncState::Dropped);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn manga_state_in_progress_via_sync_chapter_list_job(pool: PgPool) {
+    seed_source(&pool).await;
+    let m = insert_manga(&pool, "Syncing Manga").await;
+    insert_manga_source(&pool, m, "smk-1", false).await;
+    // sync_chapter_list payload carries manga_id directly.
+    insert_job(
+        &pool,
+        json!({
+            "kind": "sync_chapter_list",
+            "source_id": SOURCE_ID,
+            "manga_id": m.to_string(),
+            "source_manga_key": "smk-1",
+        }),
+        "pending",
+    )
+    .await;
+
+    let (rows, _) = repo::admin_view::list_mangas_with_sync_state(
+        &pool,
+        &repo::admin_view::ListAdminMangasQuery {
+            limit: 50,
+            ..Default::default()
+        },
+    )
+    .await
+    .unwrap();
+    assert_eq!(rows[0].sync_state, mangalord::domain::MangaSyncState::InProgress);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn manga_state_in_progress_via_sync_manga_job(pool: PgPool) {
+    // The trickier branch: sync_manga payload is keyed by
+    // source_manga_key, NOT manga_id — must join through manga_sources.
+    seed_source(&pool).await;
+    let m = insert_manga(&pool, "Metadata-Refreshing Manga").await;
+    insert_manga_source(&pool, m, "smk-key-42", false).await;
+    insert_job(
+        &pool,
+        json!({
+            "kind": "sync_manga",
+            "source_id": SOURCE_ID,
+            "source_manga_key": "smk-key-42",
+        }),
+        "running",
+    )
+    .await;
+
+    let (rows, _) = repo::admin_view::list_mangas_with_sync_state(
+        &pool,
+        &repo::admin_view::ListAdminMangasQuery {
+            limit: 50,
+            ..Default::default()
+        },
+    )
+    .await
+    .unwrap();
+    assert_eq!(rows[0].sync_state, mangalord::domain::MangaSyncState::InProgress);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn manga_list_filters_by_sync_state(pool: PgPool) {
+    seed_source(&pool).await;
+    let m_synced = insert_manga(&pool, "AAA Synced").await;
+    insert_manga_source(&pool, m_synced, "smk-a", false).await;
+    let m_dropped = insert_manga(&pool, "BBB Dropped").await;
+    insert_manga_source(&pool, m_dropped, "smk-b", true).await;
+
+    let (rows, total) = repo::admin_view::list_mangas_with_sync_state(
+        &pool,
+        &repo::admin_view::ListAdminMangasQuery {
+            sync_state: Some(mangalord::domain::MangaSyncState::Dropped),
+            limit: 50,
+            ..Default::default()
+        },
+    )
+    .await
+    .unwrap();
+    assert_eq!(total, 1);
+    assert_eq!(rows.len(), 1);
+    assert_eq!(rows[0].id, m_dropped);
+}
+
+// ---- chapter sync state ----------------------------------------------------
+
+#[sqlx::test(migrations = "./migrations")]
+async fn chapter_state_synced_when_pages_present(pool: PgPool) {
+    seed_source(&pool).await;
+    let m = insert_manga(&pool, "M").await;
+    insert_manga_source(&pool, m, "smk", false).await;
+    let c = insert_chapter(&pool, m, 1, 12).await;
+    insert_chapter_source(&pool, c, "ckey-1", false).await;
+
+    let rows = fetch_chapter_rows(&pool, m).await;
+    assert_eq!(rows.len(), 1);
+    assert_eq!(rows[0].id, c);
+    assert_eq!(rows[0].sync_state, mangalord::domain::ChapterSyncState::Synced);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn chapter_state_not_downloaded_when_page_count_zero(pool: PgPool) {
+    seed_source(&pool).await;
+    let m = insert_manga(&pool, "M").await;
+    let c = insert_chapter(&pool, m, 1, 0).await;
+    insert_chapter_source(&pool, c, "ckey-1", false).await;
+
+    let rows = fetch_chapter_rows(&pool, m).await;
+    assert_eq!(
+        rows[0].sync_state,
+        mangalord::domain::ChapterSyncState::NotDownloaded
+    );
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn chapter_state_downloading_when_job_in_flight(pool: PgPool) {
+    seed_source(&pool).await;
+    let m = insert_manga(&pool, "M").await;
+    let c = insert_chapter(&pool, m, 1, 0).await;
+    insert_chapter_source(&pool, c, "ckey-1", false).await;
+    insert_job(
+        &pool,
+        json!({
+            "kind": "sync_chapter_content",
+            "source_id": SOURCE_ID,
+            "chapter_id": c.to_string(),
+            "source_chapter_key": "ckey-1",
+        }),
+        "running",
+    )
+    .await;
+
+    let rows = fetch_chapter_rows(&pool, m).await;
+    assert_eq!(
+        rows[0].sync_state,
+        mangalord::domain::ChapterSyncState::Downloading
+    );
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn chapter_state_dropped_when_all_sources_dropped(pool: PgPool) {
+    seed_source(&pool).await;
+    let m = insert_manga(&pool, "M").await;
+    let c = insert_chapter(&pool, m, 1, 0).await;
+    insert_chapter_source(&pool, c, "ckey-1", true).await;
+
+    let rows = fetch_chapter_rows(&pool, m).await;
+    assert_eq!(
+        rows[0].sync_state,
+        mangalord::domain::ChapterSyncState::Dropped
+    );
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn chapter_state_failed_when_most_recent_job_dead(pool: PgPool) {
+    seed_source(&pool).await;
+    let m = insert_manga(&pool, "M").await;
+    let c = insert_chapter(&pool, m, 1, 0).await;
+    insert_chapter_source(&pool, c, "ckey-1", false).await;
+    insert_job(
+        &pool,
+        json!({
+            "kind": "sync_chapter_content",
+            "source_id": SOURCE_ID,
+            "chapter_id": c.to_string(),
+            "source_chapter_key": "ckey-1",
+        }),
+        "dead",
+    )
+    .await;
+
+    let rows = fetch_chapter_rows(&pool, m).await;
+    assert_eq!(
+        rows[0].sync_state,
+        mangalord::domain::ChapterSyncState::Failed
+    );
+}
+
+// ---- HTTP-level happy-path + gate ------------------------------------------
+
+#[sqlx::test(migrations = "./migrations")]
+async fn http_list_mangas_returns_paged_with_state(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (_admin, cookie) = seed_admin(&pool, &h.app).await;
+    seed_source(&pool).await;
+    let m = insert_manga(&pool, "Hello").await;
+    insert_manga_source(&pool, m, "smk", false).await;
+
+    let resp = h
+        .app
+        .oneshot(common::get_with_cookie(
+            "/api/v1/admin/mangas?limit=50",
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = common::body_json(resp).await;
+    let items = body["items"].as_array().unwrap();
+    assert_eq!(items.len(), 1);
+    assert_eq!(items[0]["id"], m.to_string());
+    assert_eq!(items[0]["sync_state"], "synced");
+    assert_eq!(items[0]["chapter_count"], 0);
+    assert_eq!(body["page"]["total"], 1);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn http_list_mangas_rejects_unknown_sync_state(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (_admin, cookie) = seed_admin(&pool, &h.app).await;
+    let resp = h
+        .app
+        .oneshot(common::get_with_cookie(
+            "/api/v1/admin/mangas?sync_state=bogus",
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::BAD_REQUEST);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn http_list_chapters_returns_per_chapter_state(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (_admin, cookie) = seed_admin(&pool, &h.app).await;
+    seed_source(&pool).await;
+    let m = insert_manga(&pool, "M").await;
+    let c1 = insert_chapter(&pool, m, 1, 12).await;
+    let c2 = insert_chapter(&pool, m, 2, 0).await;
+    insert_chapter_source(&pool, c1, "ck1", false).await;
+    insert_chapter_source(&pool, c2, "ck2", false).await;
+
+    let resp = h
+        .app
+        .oneshot(common::get_with_cookie(
+            &format!("/api/v1/admin/mangas/{m}/chapters"),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = common::body_json(resp).await;
+    let items = body["items"].as_array().unwrap();
+    assert_eq!(items.len(), 2);
+    assert_eq!(items[0]["id"], c1.to_string());
+    assert_eq!(items[0]["sync_state"], "synced");
+    assert_eq!(items[1]["id"], c2.to_string());
+    assert_eq!(items[1]["sync_state"], "not_downloaded");
+    assert_eq!(body["page"]["total"], 2);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn http_list_chapters_caps_limit_at_500(pool: PgPool) {
+    // The handler clamps limit to [1, 500] so a long-runner with
+    // thousands of chapters can't be turned into a request-stall by an
+    // admin (or by a curious admin tab) just clicking expand.
+    let h = common::harness(pool.clone());
+    let (_admin, cookie) = seed_admin(&pool, &h.app).await;
+    seed_source(&pool).await;
+    let m = insert_manga(&pool, "M").await;
+    for n in 1..=3 {
+        let _c = insert_chapter(&pool, m, n, 0).await;
+    }
+    let resp = h
+        .app
+        .oneshot(common::get_with_cookie(
+            &format!("/api/v1/admin/mangas/{m}/chapters?limit=999"),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["page"]["limit"], 500, "limit must clamp to 500");
+    assert_eq!(body["items"].as_array().unwrap().len(), 3);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn http_list_chapters_paginates(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (_admin, cookie) = seed_admin(&pool, &h.app).await;
+    seed_source(&pool).await;
+    let m = insert_manga(&pool, "M").await;
+    for n in 1..=5 {
+        let _c = insert_chapter(&pool, m, n, 0).await;
+    }
+
+    let resp = h
+        .app
+        .clone()
+        .oneshot(common::get_with_cookie(
+            &format!("/api/v1/admin/mangas/{m}/chapters?limit=2&offset=2"),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    let body = common::body_json(resp).await;
+    let items = body["items"].as_array().unwrap();
+    assert_eq!(items.len(), 2);
+    // Ordered by chapter number ascending; offset=2 skips chapters 1 & 2.
+    assert_eq!(items[0]["number"], 3);
+    assert_eq!(items[1]["number"], 4);
+    assert_eq!(body["page"]["total"], 5);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn http_list_chapters_returns_404_for_unknown_manga(pool: PgPool) {
+    // Regression: used to return 200 [] for a non-existent manga,
+    // which silently rendered "No chapters." for a typo'd / deleted id.
+    let h = common::harness(pool.clone());
+    let (_admin, cookie) = seed_admin(&pool, &h.app).await;
+    let resp = h
+        .app
+        .oneshot(common::get_with_cookie(
+            &format!("/api/v1/admin/mangas/{}/chapters", Uuid::new_v4()),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::NOT_FOUND);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn chapter_state_synced_when_pages_present_even_with_dead_job(pool: PgPool) {
+    // Regression: the old CASE prioritised the dead-job branch above
+    // the page_count check, so a chapter with pages on disk AND a
+    // historical dead job (e.g. from a re-download attempt that
+    // crashed) flipped to Failed — contradicting Synced's "downloaded
+    // at some point" contract.
+    seed_source(&pool).await;
+    let m = insert_manga(&pool, "M").await;
+    let c = insert_chapter(&pool, m, 1, 12).await; // pages present
+    insert_chapter_source(&pool, c, "ckey-1", false).await;
+    insert_job(
+        &pool,
+        json!({
+            "kind": "sync_chapter_content",
+            "source_id": SOURCE_ID,
+            "chapter_id": c.to_string(),
+            "source_chapter_key": "ckey-1",
+        }),
+        "dead",
+    )
+    .await;
+
+    let rows = fetch_chapter_rows(&pool, m).await;
+    assert_eq!(
+        rows[0].sync_state,
+        mangalord::domain::ChapterSyncState::Synced,
+        "pages on disk override historical dead-job noise"
+    );
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn http_list_mangas_requires_admin(pool: PgPool) {
+    let h = common::harness(pool);
+    let (_u, cookie) = common::register_user(&h.app).await;
+    let resp = h
+        .app
+        .oneshot(common::get_with_cookie("/api/v1/admin/mangas", &cookie))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::FORBIDDEN);
+}

backend/tests/api_admin_resync.rs

@@ -0,0 +1,350 @@
+//! Integration tests for the admin force-resync endpoints.
+//!
+//! Real resync work requires Chromium, so these tests swap in a stub
+//! [`ResyncService`] to assert the handler-level contract: routing,
+//! admin gate, 503 when the daemon is disabled, 404 / 422 mapping for
+//! missing-resource / no-source cases, and the audit-log side effect.
+
+mod common;
+
+use std::sync::Arc;
+use std::sync::atomic::{AtomicUsize, Ordering};
+
+use async_trait::async_trait;
+use axum::http::StatusCode;
+use serde_json::json;
+use sqlx::PgPool;
+use tower::ServiceExt;
+use uuid::Uuid;
+
+use mangalord::crawler::resync::{
+    ChapterResyncOutcome, MangaResyncOutcome, ResyncError, ResyncService,
+};
+use mangalord::repo;
+use mangalord::repo::crawler::UpsertStatus;
+
+/// Stub that records call counts and returns a canned outcome.
+struct StubResync {
+    manga_calls: AtomicUsize,
+    chapter_calls: AtomicUsize,
+    /// When true, returns NoMangaSource / NoChapterSource.
+    no_source: bool,
+}
+
+impl StubResync {
+    fn new() -> Arc<Self> {
+        Arc::new(Self {
+            manga_calls: AtomicUsize::new(0),
+            chapter_calls: AtomicUsize::new(0),
+            no_source: false,
+        })
+    }
+    fn no_source() -> Arc<Self> {
+        Arc::new(Self {
+            manga_calls: AtomicUsize::new(0),
+            chapter_calls: AtomicUsize::new(0),
+            no_source: true,
+        })
+    }
+}
+
+#[async_trait]
+impl ResyncService for StubResync {
+    async fn resync_manga(&self, manga_id: Uuid) -> anyhow::Result<MangaResyncOutcome> {
+        self.manga_calls.fetch_add(1, Ordering::SeqCst);
+        if self.no_source {
+            return Err(ResyncError::NoMangaSource.into());
+        }
+        Ok(MangaResyncOutcome {
+            manga_id,
+            metadata_status: UpsertStatus::Updated,
+            cover_fetched: true,
+        })
+    }
+    async fn resync_chapter(&self, chapter_id: Uuid) -> anyhow::Result<ChapterResyncOutcome> {
+        self.chapter_calls.fetch_add(1, Ordering::SeqCst);
+        if self.no_source {
+            return Err(ResyncError::NoChapterSource.into());
+        }
+        Ok(ChapterResyncOutcome::Fetched {
+            chapter_id,
+            pages: 7,
+        })
+    }
+}
+
+async fn promote_admin(pool: &PgPool, username: &str) {
+    let u = repo::user::find_by_username(pool, username)
+        .await
+        .unwrap()
+        .unwrap();
+    repo::user::set_is_admin_unchecked(pool, u.id, true)
+        .await
+        .unwrap();
+}
+
+async fn insert_manga(pool: &PgPool, title: &str) -> Uuid {
+    let (id,): (Uuid,) = sqlx::query_as(
+        "INSERT INTO mangas (title, status, alt_titles) VALUES ($1, 'ongoing', ARRAY[]::text[]) RETURNING id",
+    )
+    .bind(title)
+    .fetch_one(pool)
+    .await
+    .unwrap();
+    id
+}
+
+async fn insert_chapter(pool: &PgPool, manga_id: Uuid, number: i32, pages: i32) -> Uuid {
+    let (id,): (Uuid,) = sqlx::query_as(
+        "INSERT INTO chapters (manga_id, number, title, page_count) VALUES ($1, $2, NULL, $3) RETURNING id",
+    )
+    .bind(manga_id)
+    .bind(number)
+    .bind(pages)
+    .fetch_one(pool)
+    .await
+    .unwrap();
+    id
+}
+
+// ----- manga resync ---------------------------------------------------------
+
+#[sqlx::test(migrations = "./migrations")]
+async fn manga_resync_calls_service_and_returns_refreshed_detail(pool: PgPool) {
+    let stub = StubResync::new();
+    let h = common::harness_with_resync(pool.clone(), stub.clone());
+    let (username, cookie) = common::register_user(&h.app).await;
+    promote_admin(&pool, &username).await;
+    let manga_id = insert_manga(&pool, "Hello").await;
+
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            &format!("/api/v1/admin/mangas/{manga_id}/resync"),
+            json!({}),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = common::body_json(resp).await;
+    // Stub returned Updated + cover_fetched=true.
+    assert_eq!(body["metadata_status"], "updated");
+    assert_eq!(body["cover_fetched"], true);
+    // Response includes the refreshed manga detail.
+    assert_eq!(body["manga"]["id"], manga_id.to_string());
+    assert_eq!(body["manga"]["title"], "Hello");
+
+    assert_eq!(stub.manga_calls.load(Ordering::SeqCst), 1);
+
+    // Audit row written.
+    let (audit_count,): (i64,) =
+        sqlx::query_as("SELECT count(*) FROM admin_audit WHERE action = 'manga_resync' AND target_id = $1")
+            .bind(manga_id)
+            .fetch_one(&pool)
+            .await
+            .unwrap();
+    assert_eq!(audit_count, 1);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn manga_resync_returns_404_for_unknown_id(pool: PgPool) {
+    let stub = StubResync::new();
+    let h = common::harness_with_resync(pool.clone(), stub.clone());
+    let (username, cookie) = common::register_user(&h.app).await;
+    promote_admin(&pool, &username).await;
+
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            &format!("/api/v1/admin/mangas/{}/resync", Uuid::new_v4()),
+            json!({}),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::NOT_FOUND);
+    // Service must not have been called when the manga doesn't exist.
+    assert_eq!(stub.manga_calls.load(Ordering::SeqCst), 0);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn manga_resync_maps_no_source_to_422(pool: PgPool) {
+    let stub = StubResync::no_source();
+    let h = common::harness_with_resync(pool.clone(), stub);
+    let (username, cookie) = common::register_user(&h.app).await;
+    promote_admin(&pool, &username).await;
+    let manga_id = insert_manga(&pool, "Manual upload, no crawler source").await;
+
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            &format!("/api/v1/admin/mangas/{manga_id}/resync"),
+            json!({}),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::UNPROCESSABLE_ENTITY);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["error"]["details"]["manga"], "no_source");
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn manga_resync_returns_503_when_daemon_disabled(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (username, cookie) = common::register_user(&h.app).await;
+    promote_admin(&pool, &username).await;
+    let manga_id = insert_manga(&pool, "Z").await;
+
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            &format!("/api/v1/admin/mangas/{manga_id}/resync"),
+            json!({}),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::SERVICE_UNAVAILABLE);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["error"]["code"], "service_unavailable");
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn manga_resync_requires_admin(pool: PgPool) {
+    let stub = StubResync::new();
+    let h = common::harness_with_resync(pool.clone(), stub);
+    // Non-admin user.
+    let (_u, cookie) = common::register_user(&h.app).await;
+    let manga_id = insert_manga(&pool, "M").await;
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            &format!("/api/v1/admin/mangas/{manga_id}/resync"),
+            json!({}),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::FORBIDDEN);
+}
+
+// ----- chapter resync -------------------------------------------------------
+
+#[sqlx::test(migrations = "./migrations")]
+async fn chapter_resync_calls_service_and_returns_refreshed_chapter(pool: PgPool) {
+    let stub = StubResync::new();
+    let h = common::harness_with_resync(pool.clone(), stub.clone());
+    let (username, cookie) = common::register_user(&h.app).await;
+    promote_admin(&pool, &username).await;
+    let manga_id = insert_manga(&pool, "M").await;
+    let chapter_id = insert_chapter(&pool, manga_id, 1, 0).await;
+
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            &format!("/api/v1/admin/chapters/{chapter_id}/resync"),
+            json!({}),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["outcome"], "fetched");
+    assert_eq!(body["pages"], 7);
+    assert_eq!(body["chapter"]["id"], chapter_id.to_string());
+    assert_eq!(stub.chapter_calls.load(Ordering::SeqCst), 1);
+
+    let (audit_count,): (i64,) = sqlx::query_as(
+        "SELECT count(*) FROM admin_audit WHERE action = 'chapter_resync' AND target_id = $1",
+    )
+    .bind(chapter_id)
+    .fetch_one(&pool)
+    .await
+    .unwrap();
+    assert_eq!(audit_count, 1);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn chapter_resync_returns_404_for_unknown_id(pool: PgPool) {
+    let stub = StubResync::new();
+    let h = common::harness_with_resync(pool.clone(), stub.clone());
+    let (username, cookie) = common::register_user(&h.app).await;
+    promote_admin(&pool, &username).await;
+
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            &format!("/api/v1/admin/chapters/{}/resync", Uuid::new_v4()),
+            json!({}),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::NOT_FOUND);
+    assert_eq!(stub.chapter_calls.load(Ordering::SeqCst), 0);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn chapter_resync_maps_no_source_to_422(pool: PgPool) {
+    let stub = StubResync::no_source();
+    let h = common::harness_with_resync(pool.clone(), stub);
+    let (username, cookie) = common::register_user(&h.app).await;
+    promote_admin(&pool, &username).await;
+    let manga_id = insert_manga(&pool, "M").await;
+    let chapter_id = insert_chapter(&pool, manga_id, 1, 0).await;
+
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            &format!("/api/v1/admin/chapters/{chapter_id}/resync"),
+            json!({}),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::UNPROCESSABLE_ENTITY);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["error"]["details"]["chapter"], "no_source");
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn chapter_resync_returns_503_when_daemon_disabled(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (username, cookie) = common::register_user(&h.app).await;
+    promote_admin(&pool, &username).await;
+    let manga_id = insert_manga(&pool, "M").await;
+    let chapter_id = insert_chapter(&pool, manga_id, 1, 0).await;
+
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            &format!("/api/v1/admin/chapters/{chapter_id}/resync"),
+            json!({}),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::SERVICE_UNAVAILABLE);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn chapter_resync_requires_admin(pool: PgPool) {
+    let stub = StubResync::new();
+    let h = common::harness_with_resync(pool.clone(), stub);
+    let (_u, cookie) = common::register_user(&h.app).await;
+    let manga_id = insert_manga(&pool, "M").await;
+    let chapter_id = insert_chapter(&pool, manga_id, 1, 0).await;
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            &format!("/api/v1/admin/chapters/{chapter_id}/resync"),
+            json!({}),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::FORBIDDEN);
+}

backend/tests/api_admin_role.rs

@@ -0,0 +1,258 @@
+//! PR 1 (feat/admin-role) integration tests.
+//!
+//! Covers: `bootstrap_admin` semantics, `is_admin` exposed on /auth/me,
+//! and the `RequireAdmin` extractor's 401/403/200 matrix — including the
+//! load-bearing decision that Bearer-authed callers can NEVER reach an
+//! admin-guarded route, even when the underlying user IS admin.
+
+mod common;
+
+use std::sync::Arc;
+
+use axum::http::StatusCode;
+use axum::routing::get;
+use axum::{Json, Router};
+use serde_json::json;
+use sqlx::PgPool;
+use tempfile::TempDir;
+use tower::ServiceExt;
+
+use mangalord::api;
+use mangalord::app::AppState;
+use mangalord::auth::extractor::RequireAdmin;
+use mangalord::auth::rate_limit::AuthRateLimiter;
+use mangalord::config::{AuthConfig, UploadConfig};
+use mangalord::repo;
+use mangalord::storage::{LocalStorage, Storage};
+
+/// Test-only handler guarded by `RequireAdmin`. Lets the test suite assert
+/// the extractor's behaviour end-to-end without depending on an admin
+/// endpoint existing yet (those land in PR 2+).
+async fn admin_only_handler(RequireAdmin(user): RequireAdmin) -> Json<serde_json::Value> {
+    Json(json!({ "username": user.username, "is_admin": user.is_admin }))
+}
+
+/// Build a router that exposes the production /api/v1/* AND a test-only
+/// `/_test/admin_only` route guarded by `RequireAdmin`. Pool is consumed;
+/// callers that want to inspect the DB after a request should clone it.
+fn admin_test_router(pool: PgPool) -> (Router, TempDir) {
+    let storage_dir = tempfile::tempdir().expect("tempdir");
+    let storage: Arc<dyn Storage> = Arc::new(LocalStorage::new(storage_dir.path()));
+    let auth = AuthConfig {
+        cookie_secure: false,
+        ..AuthConfig::default()
+    };
+    let auth_limiter = Arc::new(AuthRateLimiter::new(auth.rate_limit));
+    let state = AppState {
+        db: pool,
+        storage,
+        auth,
+        upload: UploadConfig::default(),
+        auth_limiter,
+        resync: None,
+    };
+    let app = Router::new()
+        .nest("/api/v1", api::routes())
+        .route("/_test/admin_only", get(admin_only_handler))
+        .with_state(state);
+    (app, storage_dir)
+}
+
+// ---- bootstrap_admin -------------------------------------------------------
+
+#[sqlx::test(migrations = "./migrations")]
+async fn bootstrap_creates_admin_when_user_missing(pool: PgPool) {
+    repo::user::bootstrap_admin(&pool, "root", "hunter2hunter2")
+        .await
+        .expect("bootstrap on empty DB");
+
+    let user = repo::user::find_by_username(&pool, "root")
+        .await
+        .unwrap()
+        .expect("root user exists after bootstrap");
+    assert!(user.is_admin, "bootstrap must set is_admin = true on creation");
+
+    // Password hash must verify the env-supplied password (and not be empty).
+    assert!(
+        mangalord::auth::password::verify_password("hunter2hunter2", &user.password_hash),
+        "bootstrap-created user must accept the env-supplied password"
+    );
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn bootstrap_promotes_existing_user_without_touching_password(pool: PgPool) {
+    // Pre-existing user, not admin. Use the real register path so the
+    // hash format matches production exactly.
+    let (app, _td) = admin_test_router(pool.clone());
+    let resp = app
+        .oneshot(common::post_json(
+            "/api/v1/auth/register",
+            json!({ "username": "preexisting", "password": "originalpw1234" }),
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::CREATED);
+
+    let before = repo::user::find_by_username(&pool, "preexisting")
+        .await
+        .unwrap()
+        .unwrap();
+    assert!(!before.is_admin);
+    let original_hash = before.password_hash.clone();
+
+    // Bootstrap with a DIFFERENT password — must not overwrite the hash.
+    repo::user::bootstrap_admin(&pool, "preexisting", "envpw_should_be_ignored")
+        .await
+        .expect("bootstrap on existing user");
+
+    let after = repo::user::find_by_username(&pool, "preexisting")
+        .await
+        .unwrap()
+        .unwrap();
+    assert!(after.is_admin, "bootstrap must promote existing user");
+    assert_eq!(
+        after.password_hash, original_hash,
+        "bootstrap must NOT overwrite the existing password hash"
+    );
+    assert!(
+        mangalord::auth::password::verify_password("originalpw1234", &after.password_hash),
+        "original password must still verify after bootstrap"
+    );
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn bootstrap_is_idempotent(pool: PgPool) {
+    repo::user::bootstrap_admin(&pool, "root", "hunter2hunter2")
+        .await
+        .expect("first bootstrap");
+    repo::user::bootstrap_admin(&pool, "root", "hunter2hunter2")
+        .await
+        .expect("second bootstrap is no-op");
+
+    // Exactly one row, still admin.
+    let (count,): (i64,) = sqlx::query_as("SELECT COUNT(*) FROM users WHERE username = $1")
+        .bind("root")
+        .fetch_one(&pool)
+        .await
+        .unwrap();
+    assert_eq!(count, 1);
+}
+
+// ---- /api/v1/auth/me exposes is_admin --------------------------------------
+
+#[sqlx::test(migrations = "./migrations")]
+async fn auth_me_response_includes_is_admin(pool: PgPool) {
+    let (app, _td) = admin_test_router(pool.clone());
+    let (_username, cookie) = common::register_user(&app).await;
+    let resp = app
+        .oneshot(common::get_with_cookie("/api/v1/auth/me", &cookie))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = common::body_json(resp).await;
+    assert_eq!(
+        body["user"]["is_admin"], false,
+        "freshly-registered users default to is_admin=false"
+    );
+}
+
+// ---- RequireAdmin: 401 / 403 / 200 matrix ----------------------------------
+
+#[sqlx::test(migrations = "./migrations")]
+async fn require_admin_rejects_unauthenticated(pool: PgPool) {
+    let (app, _td) = admin_test_router(pool);
+    let resp = app
+        .oneshot(common::get("/_test/admin_only"))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::UNAUTHORIZED);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn require_admin_rejects_non_admin_cookie(pool: PgPool) {
+    let (app, _td) = admin_test_router(pool);
+    let (_username, cookie) = common::register_user(&app).await;
+    let resp = app
+        .oneshot(common::get_with_cookie("/_test/admin_only", &cookie))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::FORBIDDEN);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["error"]["code"], "forbidden");
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn require_admin_accepts_admin_cookie(pool: PgPool) {
+    let (app, _td) = admin_test_router(pool.clone());
+    let (username, cookie) = common::register_user(&app).await;
+    // Promote via the repo (the admin-users API doesn't exist yet).
+    let u = repo::user::find_by_username(&pool, &username)
+        .await
+        .unwrap()
+        .unwrap();
+    repo::user::set_is_admin_unchecked(&pool, u.id, true).await.unwrap();
+
+    let resp = app
+        .oneshot(common::get_with_cookie("/_test/admin_only", &cookie))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["username"], username);
+    assert_eq!(body["is_admin"], true);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn require_admin_rejects_bearer_token_even_for_admin_user(pool: PgPool) {
+    // Key privilege-escalation test: an API token belonging to an admin user
+    // must NOT grant admin authority. Bot tokens are excluded from admin
+    // routes by design (the RequireAdmin extractor only accepts session
+    // cookies). See cross-cutting decision #1 in the PR plan.
+    let (app, _td) = admin_test_router(pool.clone());
+    let (username, cookie) = common::register_user(&app).await;
+
+    // Promote to admin and mint an API token (the existing /auth/tokens
+    // endpoint authenticates via the same cookie).
+    let u = repo::user::find_by_username(&pool, &username)
+        .await
+        .unwrap()
+        .unwrap();
+    repo::user::set_is_admin_unchecked(&pool, u.id, true).await.unwrap();
+
+    let resp = app
+        .clone()
+        .oneshot(common::post_json_with_cookie(
+            "/api/v1/auth/tokens",
+            json!({ "name": "test-bot" }),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::CREATED);
+    let body = common::body_json(resp).await;
+    let token = body["bearer"]
+        .as_str()
+        .expect("raw bearer token in response")
+        .to_string();
+
+    // Sanity: the bearer DOES work on a non-admin endpoint (proves the
+    // token is valid, isolating the failure below to the admin guard).
+    let resp = app
+        .clone()
+        .oneshot(common::get_with_bearer("/api/v1/auth/me", &token))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+
+    // Same token, same admin user, but on the admin-guarded route → 401
+    // (no session cookie present at all from the extractor's POV).
+    let resp = app
+        .oneshot(common::get_with_bearer("/_test/admin_only", &token))
+        .await
+        .unwrap();
+    assert_eq!(
+        resp.status(),
+        StatusCode::UNAUTHORIZED,
+        "Bearer-authed admin must NOT pass the RequireAdmin guard"
+    );
+}

backend/tests/api_admin_system.rs

@@ -0,0 +1,96 @@
+//! PR 4 (feat/admin-system-api) integration tests.
+//!
+//! Shape-only assertions — we don't mock the system, just call the
+//! endpoint and check the response envelope. Threshold-triggering of
+//! alerts would require faking statvfs / sysinfo, which is more
+//! plumbing than the test gives back.
+
+mod common;
+
+use axum::http::StatusCode;
+use axum::Router;
+use sqlx::PgPool;
+use tower::ServiceExt;
+
+use mangalord::repo;
+
+async fn seed_admin(pool: &PgPool, app: &Router) -> String {
+    let (username, cookie) = common::register_user(app).await;
+    let u = repo::user::find_by_username(pool, &username)
+        .await
+        .unwrap()
+        .unwrap();
+    repo::user::set_is_admin_unchecked(pool, u.id, true).await.unwrap();
+    cookie
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn requires_admin(pool: PgPool) {
+    let h = common::harness(pool);
+    let (_u, cookie) = common::register_user(&h.app).await;
+    let resp = h
+        .app
+        .oneshot(common::get_with_cookie("/api/v1/admin/system", &cookie))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::FORBIDDEN);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn unauthenticated_request_is_rejected(pool: PgPool) {
+    let h = common::harness(pool);
+    let resp = h
+        .app
+        .oneshot(common::get("/api/v1/admin/system"))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::UNAUTHORIZED);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn returns_disk_memory_cpu_alerts_shape(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let cookie = seed_admin(&pool, &h.app).await;
+
+    let resp = h
+        .app
+        .oneshot(common::get_with_cookie("/api/v1/admin/system", &cookie))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = common::body_json(resp).await;
+
+    // Disk: harness uses LocalStorage on a tempdir, so disk SHOULD be
+    // populated. Validate the field shape and percent range.
+    let disk = body
+        .get("disk")
+        .expect("disk key present")
+        .as_object()
+        .expect("disk is an object (LocalStorage exposes a path)");
+    assert!(disk["total_bytes"].as_u64().unwrap() > 0);
+    let pct = disk["percent_used"].as_f64().unwrap();
+    assert!(
+        (0.0..=100.0).contains(&pct),
+        "percent_used outside [0,100]: {pct}"
+    );
+
+    let mem = body.get("memory").expect("memory key").as_object().unwrap();
+    assert!(mem["total_bytes"].as_u64().unwrap() > 0);
+    let mpct = mem["percent_used"].as_f64().unwrap();
+    assert!((0.0..=100.0).contains(&mpct));
+
+    let cpu = body.get("cpu").expect("cpu key").as_object().unwrap();
+    let cpu_pct = cpu["percent_used"].as_f64().unwrap();
+    assert!(
+        (0.0..=100.0).contains(&cpu_pct),
+        "cpu out of range: {cpu_pct}"
+    );
+
+    let alerts = body.get("alerts").expect("alerts key").as_array().unwrap();
+    // Don't assert on length — the box may genuinely be >90% on memory
+    // when the test runs. Just confirm shape of any present entry.
+    for alert in alerts {
+        assert!(alert["level"].is_string());
+        assert!(alert["message"].is_string());
+    }
+}

backend/tests/api_admin_users.rs

@@ -0,0 +1,605 @@
+//! PR 2 (feat/admin-users-api) integration tests.
+//!
+//! Exercises list / delete / promote-demote on /api/v1/admin/users:
+//! pagination + search, the RequireAdmin gate, self-protection,
+//! last-admin invariant (including the parallel-demote race that
+//! `pg_advisory_xact_lock` + recount-inside-tx guards against), and
+//! that audit rows land in `admin_audit` only on successful commit.
+//!
+//! Note on the last-admin invariant: the *serial* path via HTTP is
+//! structurally unreachable — the only configuration that would hit the
+//! "would orphan admins" branch requires the actor to be the lone admin
+//! demoting themselves, which the self-guard fires on first. So the
+//! last-admin checks below call the repo directly to exercise the
+//! invariant; the HTTP race scenario is covered by
+//! `parallel_demotes_cannot_orphan_admins`.
+
+mod common;
+
+use axum::http::StatusCode;
+use axum::Router;
+use serde_json::json;
+use sqlx::PgPool;
+use tower::ServiceExt;
+use uuid::Uuid;
+
+use mangalord::error::AppError;
+use mangalord::repo;
+
+/// Register a user via the public API and immediately promote them via
+/// the repo. Returns (username, session cookie, user_id) — the common
+/// "I need a logged-in admin" prelude.
+async fn seed_admin(pool: &PgPool, app: &Router) -> (String, String, Uuid) {
+    let (username, cookie) = common::register_user(app).await;
+    let u = repo::user::find_by_username(pool, &username)
+        .await
+        .unwrap()
+        .unwrap();
+    repo::user::set_is_admin_unchecked(pool, u.id, true).await.unwrap();
+    (username, cookie, u.id)
+}
+
+// ---- RequireAdmin gate -----------------------------------------------------
+
+#[sqlx::test(migrations = "./migrations")]
+async fn list_requires_admin(pool: PgPool) {
+    let h = common::harness(pool);
+    let (_username, cookie) = common::register_user(&h.app).await;
+    let resp = h
+        .app
+        .oneshot(common::get_with_cookie("/api/v1/admin/users", &cookie))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::FORBIDDEN);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn delete_requires_admin(pool: PgPool) {
+    let h = common::harness(pool);
+    let (_username, cookie) = common::register_user(&h.app).await;
+    let resp = h
+        .app
+        .oneshot(common::delete_with_cookie(
+            &format!("/api/v1/admin/users/{}", Uuid::new_v4()),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::FORBIDDEN);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn patch_requires_admin(pool: PgPool) {
+    let h = common::harness(pool);
+    let (_username, cookie) = common::register_user(&h.app).await;
+    let resp = h
+        .app
+        .oneshot(common::patch_json_with_cookie(
+            &format!("/api/v1/admin/users/{}", Uuid::new_v4()),
+            json!({ "is_admin": true }),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::FORBIDDEN);
+}
+
+// ---- list with search and pagination ---------------------------------------
+
+#[sqlx::test(migrations = "./migrations")]
+async fn list_returns_paginated_users(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (_admin_name, cookie, _) = seed_admin(&pool, &h.app).await;
+    let _u1 = common::register_user(&h.app).await;
+    let _u2 = common::register_user(&h.app).await;
+    let _u3 = common::register_user(&h.app).await;
+
+    let resp = h
+        .app
+        .oneshot(common::get_with_cookie(
+            "/api/v1/admin/users?limit=2&offset=0",
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = common::body_json(resp).await;
+    let items = body["items"].as_array().expect("items array");
+    assert_eq!(items.len(), 2, "limit=2 should cap the page");
+    assert_eq!(body["page"]["limit"], 2);
+    assert_eq!(body["page"]["offset"], 0);
+    assert_eq!(body["page"]["total"], 4);
+    assert!(items[0].get("is_admin").is_some());
+    assert!(
+        items[0].get("password_hash").is_none(),
+        "password_hash must never leak even to other admins"
+    );
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn list_filters_by_substring_search(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (_admin_name, cookie, _) = seed_admin(&pool, &h.app).await;
+    let resp = h
+        .app
+        .clone()
+        .oneshot(common::post_json(
+            "/api/v1/auth/register",
+            json!({ "username": "zzzfindme01", "password": "hunter2hunter2" }),
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::CREATED);
+
+    let resp = h
+        .app
+        .oneshot(common::get_with_cookie(
+            "/api/v1/admin/users?search=zzzfindme",
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = common::body_json(resp).await;
+    let items = body["items"].as_array().unwrap();
+    assert_eq!(items.len(), 1, "search must narrow to the one match");
+    assert_eq!(items[0]["username"], "zzzfindme01");
+    assert_eq!(body["page"]["total"], 1);
+}
+
+// ---- self-protection -------------------------------------------------------
+
+#[sqlx::test(migrations = "./migrations")]
+async fn cannot_self_delete(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (_username, cookie, actor_id) = seed_admin(&pool, &h.app).await;
+    // Second admin so the last-admin guard isn't what triggers the conflict.
+    let (_other, _, _) = seed_admin(&pool, &h.app).await;
+
+    let resp = h
+        .app
+        .oneshot(common::delete_with_cookie(
+            &format!("/api/v1/admin/users/{actor_id}"),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::CONFLICT);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["error"]["code"], "conflict");
+    assert!(
+        body["error"]["message"]
+            .as_str()
+            .unwrap()
+            .contains("yourself"),
+        "message must call out the self-action; got {:?}",
+        body["error"]["message"]
+    );
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn cannot_self_demote(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (_username, cookie, actor_id) = seed_admin(&pool, &h.app).await;
+    let (_other, _, _) = seed_admin(&pool, &h.app).await;
+
+    let resp = h
+        .app
+        .oneshot(common::patch_json_with_cookie(
+            &format!("/api/v1/admin/users/{actor_id}"),
+            json!({ "is_admin": false }),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::CONFLICT);
+    let body = common::body_json(resp).await;
+    assert!(body["error"]["message"]
+        .as_str()
+        .unwrap()
+        .contains("yourself"));
+}
+
+// ---- last-admin invariant (repo layer, see file header) --------------------
+
+#[sqlx::test(migrations = "./migrations")]
+async fn last_admin_demote_refused_at_repo(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (_a, _, a_id) = seed_admin(&pool, &h.app).await;
+    let (_b, _, b_id) = seed_admin(&pool, &h.app).await;
+
+    // admins = {A, B}. Demote A via B (count 2 → 1) — allowed.
+    let r = repo::user::admin_safe_set_is_admin(&pool, b_id, a_id, false)
+        .await
+        .expect("first demote succeeds");
+    assert!(!r.is_admin);
+
+    // admins = {B}. Try to demote B via A (actor doesn't matter to the
+    // repo — that's the HTTP gate's job). Last-admin guard kicks in.
+    let err = repo::user::admin_safe_set_is_admin(&pool, a_id, b_id, false)
+        .await
+        .expect_err("second demote must be refused");
+    match err {
+        AppError::Conflict(m) => assert!(
+            m.contains("last admin"),
+            "expected last-admin conflict; got {m:?}"
+        ),
+        other => panic!("expected Conflict, got {other:?}"),
+    }
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn last_admin_delete_refused_at_repo(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (_a, _, a_id) = seed_admin(&pool, &h.app).await;
+    let (_b, _, b_id) = seed_admin(&pool, &h.app).await;
+
+    // admins = {A, B}. Delete A via B (count 2 → 1) — allowed.
+    repo::user::admin_safe_delete(&pool, b_id, a_id)
+        .await
+        .expect("first delete succeeds");
+
+    // admins = {B}. Try to delete B via a fresh non-admin actor. Last-
+    // admin guard kicks in.
+    let (_c, _, c_id) = {
+        let (cn, _ck) = common::register_user(&h.app).await;
+        let c = repo::user::find_by_username(&pool, &cn).await.unwrap().unwrap();
+        (cn, _ck, c.id)
+    };
+    let err = repo::user::admin_safe_delete(&pool, c_id, b_id)
+        .await
+        .expect_err("second delete must be refused");
+    match err {
+        AppError::Conflict(m) => assert!(
+            m.contains("last admin"),
+            "expected last-admin conflict; got {m:?}"
+        ),
+        other => panic!("expected Conflict, got {other:?}"),
+    }
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn parallel_demotes_cannot_orphan_admins(pool: PgPool) {
+    // The race the advisory lock + recount exists to close: two parallel
+    // demotes of two DIFFERENT admins, each reading `count = 2` and
+    // committing, would land at zero admins. With the lock the second
+    // demote sees count = 1 inside the tx and refuses.
+    let h = common::harness(pool.clone());
+    let (_a, _, a_id) = seed_admin(&pool, &h.app).await;
+    let (_b, _, b_id) = seed_admin(&pool, &h.app).await;
+
+    let pool_x = pool.clone();
+    let pool_y = pool.clone();
+    let task_x = tokio::spawn(async move {
+        repo::user::admin_safe_set_is_admin(&pool_x, a_id, b_id, false).await
+    });
+    let task_y = tokio::spawn(async move {
+        repo::user::admin_safe_set_is_admin(&pool_y, b_id, a_id, false).await
+    });
+    let r_x = task_x.await.unwrap();
+    let r_y = task_y.await.unwrap();
+
+    let outcomes = (r_x.is_ok(), r_y.is_ok());
+    assert!(
+        outcomes == (true, false) || outcomes == (false, true),
+        "exactly one of the two parallel demotes must succeed; got {outcomes:?}"
+    );
+
+    let (count,): (i64,) =
+        sqlx::query_as("SELECT COUNT(*) FROM users WHERE is_admin = true")
+            .fetch_one(&pool)
+            .await
+            .unwrap();
+    assert_eq!(count, 1, "at least one admin must remain");
+}
+
+// ---- audit log -------------------------------------------------------------
+
+#[sqlx::test(migrations = "./migrations")]
+async fn promote_writes_audit_row(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (_a_name, a_cookie, a_id) = seed_admin(&pool, &h.app).await;
+    let (b_name, _b_cookie) = common::register_user(&h.app).await;
+    let b = repo::user::find_by_username(&pool, &b_name)
+        .await
+        .unwrap()
+        .unwrap();
+
+    let resp = h
+        .app
+        .oneshot(common::patch_json_with_cookie(
+            &format!("/api/v1/admin/users/{}", b.id),
+            json!({ "is_admin": true }),
+            &a_cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+
+    let rows: Vec<(Option<Uuid>, String, String, Option<Uuid>)> = sqlx::query_as(
+        "SELECT actor_user_id, action, target_kind, target_id FROM admin_audit",
+    )
+    .fetch_all(&pool)
+    .await
+    .unwrap();
+    assert_eq!(rows.len(), 1);
+    let (actor, action, kind, target) = rows.into_iter().next().unwrap();
+    assert_eq!(actor, Some(a_id));
+    assert_eq!(action, "promote_user");
+    assert_eq!(kind, "user");
+    assert_eq!(target, Some(b.id));
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn redundant_promote_does_not_write_audit_row(pool: PgPool) {
+    // Regression: PATCH {is_admin: true} on someone already admin used
+    // to UPDATE (no-op) and still INSERT a misleading "promote_user"
+    // audit row. Should short-circuit without touching admin_audit.
+    let h = common::harness(pool.clone());
+    let (_a_name, a_cookie, _a_id) = seed_admin(&pool, &h.app).await;
+    let (b_name, _b_cookie, _b_id) = seed_admin(&pool, &h.app).await; // already admin
+
+    let b = repo::user::find_by_username(&pool, &b_name)
+        .await
+        .unwrap()
+        .unwrap();
+    let resp = h
+        .app
+        .oneshot(common::patch_json_with_cookie(
+            &format!("/api/v1/admin/users/{}", b.id),
+            json!({ "is_admin": true }),
+            &a_cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+
+    let (count,): (i64,) = sqlx::query_as("SELECT COUNT(*) FROM admin_audit")
+        .fetch_one(&pool)
+        .await
+        .unwrap();
+    assert_eq!(count, 0, "no-op promote must not write audit row");
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn delete_writes_audit_row(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (_a_name, a_cookie, a_id) = seed_admin(&pool, &h.app).await;
+    let (b_name, _b_cookie) = common::register_user(&h.app).await;
+    let b = repo::user::find_by_username(&pool, &b_name)
+        .await
+        .unwrap()
+        .unwrap();
+
+    let resp = h
+        .app
+        .oneshot(common::delete_with_cookie(
+            &format!("/api/v1/admin/users/{}", b.id),
+            &a_cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::NO_CONTENT);
+
+    let rows: Vec<(Option<Uuid>, String, String, Option<Uuid>, serde_json::Value)> =
+        sqlx::query_as(
+            "SELECT actor_user_id, action, target_kind, target_id, payload FROM admin_audit",
+        )
+        .fetch_all(&pool)
+        .await
+        .unwrap();
+    assert_eq!(rows.len(), 1);
+    let (actor, action, kind, target, payload) = rows.into_iter().next().unwrap();
+    assert_eq!(actor, Some(a_id));
+    assert_eq!(action, "delete_user");
+    assert_eq!(kind, "user");
+    assert_eq!(target, Some(b.id));
+    assert_eq!(payload["username"], b_name);
+    assert_eq!(payload["was_admin"], false);
+}
+
+// ---- POST /admin/users (admin-create) --------------------------------------
+
+#[sqlx::test(migrations = "./migrations")]
+async fn create_user_requires_admin(pool: PgPool) {
+    let h = common::harness(pool);
+    let (_username, cookie) = common::register_user(&h.app).await;
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            "/api/v1/admin/users",
+            json!({ "username": "newbie", "password": "hunter2hunter2" }),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::FORBIDDEN);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn create_user_unauthenticated_is_rejected(pool: PgPool) {
+    let h = common::harness(pool);
+    let resp = h
+        .app
+        .oneshot(common::post_json(
+            "/api/v1/admin/users",
+            json!({ "username": "newbie", "password": "hunter2hunter2" }),
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::UNAUTHORIZED);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn create_user_happy_path_creates_user_and_audit(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (_a_name, a_cookie, a_id) = seed_admin(&pool, &h.app).await;
+
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            "/api/v1/admin/users",
+            json!({ "username": "invited01", "password": "freshpass1234" }),
+            &a_cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::CREATED);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["username"], "invited01");
+    assert_eq!(body["is_admin"], false);
+    assert!(body["id"].as_str().is_some());
+    assert!(
+        body.get("password_hash").is_none(),
+        "password_hash must never appear in admin-create response"
+    );
+
+    let target_id =
+        Uuid::parse_str(body["id"].as_str().unwrap()).unwrap();
+    let (actor, action, kind, target, payload): (
+        Option<Uuid>,
+        String,
+        String,
+        Option<Uuid>,
+        serde_json::Value,
+    ) = sqlx::query_as(
+        "SELECT actor_user_id, action, target_kind, target_id, payload \
+           FROM admin_audit ORDER BY at DESC LIMIT 1",
+    )
+    .fetch_one(&pool)
+    .await
+    .unwrap();
+    assert_eq!(actor, Some(a_id));
+    assert_eq!(action, "create_user");
+    assert_eq!(kind, "user");
+    assert_eq!(target, Some(target_id));
+    assert_eq!(payload["username"], "invited01");
+    assert_eq!(payload["is_admin"], false);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn create_user_can_mint_an_admin_in_one_call(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (_a_name, a_cookie, _) = seed_admin(&pool, &h.app).await;
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            "/api/v1/admin/users",
+            json!({
+                "username": "newadmin",
+                "password": "freshpass1234",
+                "is_admin": true
+            }),
+            &a_cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::CREATED);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["is_admin"], true);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn create_user_returns_409_on_duplicate(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (_a_name, a_cookie, _) = seed_admin(&pool, &h.app).await;
+    // Seed an existing user via the public register path.
+    let resp = h
+        .app
+        .clone()
+        .oneshot(common::post_json(
+            "/api/v1/auth/register",
+            json!({ "username": "taken", "password": "hunter2hunter2" }),
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::CREATED);
+
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            "/api/v1/admin/users",
+            json!({ "username": "Taken", "password": "freshpass1234" }),
+            &a_cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(
+        resp.status(),
+        StatusCode::CONFLICT,
+        "case-insensitive collision via the lower(username) index"
+    );
+    let body = common::body_json(resp).await;
+    assert_eq!(body["error"]["code"], "conflict");
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn create_user_rejects_weak_password(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (_a_name, a_cookie, _) = seed_admin(&pool, &h.app).await;
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            "/api/v1/admin/users",
+            json!({ "username": "okayname", "password": "short" }),
+            &a_cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::BAD_REQUEST);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["error"]["code"], "invalid_input");
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn create_user_rejects_invalid_username(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (_a_name, a_cookie, _) = seed_admin(&pool, &h.app).await;
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            "/api/v1/admin/users",
+            json!({ "username": "bad name!", "password": "freshpass1234" }),
+            &a_cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::BAD_REQUEST);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn create_user_works_even_when_self_register_disabled(pool: PgPool) {
+    // The admin-create path must NOT be gated by ALLOW_SELF_REGISTER —
+    // that's the entire point of having an admin-create endpoint.
+    let h = common::harness_with_self_register_disabled(pool.clone());
+    // Bootstrap an admin out-of-band since self-register would refuse.
+    repo::user::bootstrap_admin(&pool, "root", "hunter2hunter2")
+        .await
+        .unwrap();
+    let resp = h
+        .app
+        .clone()
+        .oneshot(common::post_json(
+            "/api/v1/auth/login",
+            json!({ "username": "root", "password": "hunter2hunter2" }),
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let cookie = common::extract_session_cookie(&resp).unwrap();
+
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            "/api/v1/admin/users",
+            json!({ "username": "invited01", "password": "freshpass1234" }),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(
+        resp.status(),
+        StatusCode::CREATED,
+        "admin must be able to mint users even with self-register off"
+    );
+}

backend/tests/api_auth.rs

@@ -567,6 +567,166 @@ async fn user_a_cannot_delete_user_b_token(pool: PgPool) {
     assert_eq!(resp.status(), StatusCode::NO_CONTENT);
 }
 
+/// Username enumeration via login response time: an attacker probes
+/// for valid usernames by measuring how long /auth/login takes. Before
+/// the equalisation fix, the no-user branch returned 401 in <1 ms
+/// while the wrong-password branch took ~50-100 ms (the argon2 verify
+/// cost). This test asserts the no-user branch now spends at least
+/// some meaningful fraction of the wrong-password branch's time.
+///
+/// Tolerance is intentionally loose so CI variance doesn't flap the
+/// test. The unequalised gap is large enough (~50x) that even a noisy
+/// CI run with a 5x slack still catches it.
+#[sqlx::test(migrations = "./migrations")]
+async fn login_no_user_branch_runs_argon2_for_timing_equalisation(pool: PgPool) {
+    use std::time::Instant;
+
+    let h = common::harness(pool);
+
+    // Register the victim user so the wrong-password branch has a real
+    // argon2 hash to verify against.
+    let _ = h
+        .app
+        .clone()
+        .oneshot(common::post_json(
+            "/api/v1/auth/register",
+            json!({ "username": "victim", "password": "hunter2hunter2" }),
+        ))
+        .await
+        .unwrap();
+
+    // Warm-up: first login of the process initialises the dummy hash
+    // lazily. Skip that cost when measuring.
+    let _ = h
+        .app
+        .clone()
+        .oneshot(common::post_json(
+            "/api/v1/auth/login",
+            json!({ "username": "victim", "password": "wrong" }),
+        ))
+        .await
+        .unwrap();
+    let _ = h
+        .app
+        .clone()
+        .oneshot(common::post_json(
+            "/api/v1/auth/login",
+            json!({ "username": "ghost", "password": "wrong" }),
+        ))
+        .await
+        .unwrap();
+
+    // Median-of-N is more stable than a single sample.
+    async fn sample_min(
+        app: &axum::Router,
+        username: &str,
+        n: u32,
+    ) -> std::time::Duration {
+        let mut samples = Vec::with_capacity(n as usize);
+        for _ in 0..n {
+            let req = common::post_json(
+                "/api/v1/auth/login",
+                json!({ "username": username, "password": "wrong-guess" }),
+            );
+            let t = Instant::now();
+            let resp = app.clone().oneshot(req).await.unwrap();
+            let d = t.elapsed();
+            assert_eq!(resp.status(), StatusCode::UNAUTHORIZED);
+            samples.push(d);
+        }
+        // Use the minimum: it's the floor that argon2 takes, robust
+        // against unrelated stalls (DB connection acquisition, etc.).
+        *samples.iter().min().unwrap()
+    }
+
+    let wrong_pwd = sample_min(&h.app, "victim", 3).await;
+    let no_user = sample_min(&h.app, "ghost", 3).await;
+
+    // 5x slack: argon2 dominates both branches, so they should be
+    // within an order of magnitude. Unequalised, no_user would be
+    // ~50-100x faster. Asserting "no_user >= wrong_pwd / 5" catches
+    // the bug without being flaky in CI.
+    assert!(
+        no_user * 5 >= wrong_pwd,
+        "login timing leaks user existence: no_user={no_user:?}, wrong_pwd={wrong_pwd:?}"
+    );
+}
+
+/// Brute-force / spray protection: at default production limits, a
+/// tight loop of /auth/login attempts should burst through the bucket
+/// and then 429 every subsequent request until the bucket refills.
+#[sqlx::test(migrations = "./migrations")]
+async fn login_rate_limited_under_burst_pressure(pool: PgPool) {
+    let h = common::harness_with_auth_rate_limit(pool, 1, 3);
+
+    // Register a victim so the wrong-password branch is real work.
+    let _ = h
+        .app
+        .clone()
+        .oneshot(common::post_json("/api/v1/auth/register", creds("victim")))
+        .await
+        .unwrap();
+
+    // Register consumed one token from the burst-3 bucket. Fire 30
+    // wrong-password logins back-to-back; with per_sec=1 the refill
+    // is too slow to keep up and at least one must come back 429.
+    let mut saw_429 = false;
+    for _ in 0..30 {
+        let resp = h
+            .app
+            .clone()
+            .oneshot(common::post_json(
+                "/api/v1/auth/login",
+                json!({ "username": "victim", "password": "wrong" }),
+            ))
+            .await
+            .unwrap();
+        if resp.status() == StatusCode::TOO_MANY_REQUESTS {
+            // RFC 6585 §4: 429 SHOULD include a Retry-After header. The
+            // value is in seconds; with per_sec=1 the bucket needs ~1s
+            // to refill, so the header should be 1 or 2.
+            let retry_after = resp
+                .headers()
+                .get(axum::http::header::RETRY_AFTER)
+                .and_then(|v| v.to_str().ok())
+                .and_then(|s| s.parse::<u32>().ok())
+                .expect("Retry-After header present and numeric");
+            assert!(
+                retry_after >= 1,
+                "Retry-After must be at least 1s, got {retry_after}"
+            );
+            let body = common::body_json(resp).await;
+            assert_eq!(body["error"]["code"], "too_many_requests");
+            saw_429 = true;
+            break;
+        }
+    }
+    assert!(
+        saw_429,
+        "expected at least one 429 within 30 rapid login attempts"
+    );
+}
+
+/// Default (test-harness) limits are disabled, so existing tests that
+/// fire multiple auth requests don't start failing.
+#[sqlx::test(migrations = "./migrations")]
+async fn default_test_harness_does_not_rate_limit(pool: PgPool) {
+    let h = common::harness(pool);
+    for i in 0..50 {
+        let resp = h
+            .app
+            .clone()
+            .oneshot(common::post_json(
+                "/api/v1/auth/login",
+                json!({ "username": format!("nobody-{i}"), "password": "x" }),
+            ))
+            .await
+            .unwrap();
+        // None of these should be 429 — only 401.
+        assert_eq!(resp.status(), StatusCode::UNAUTHORIZED, "iter {i}");
+    }
+}
+
 #[sqlx::test(migrations = "./migrations")]
 async fn delete_unknown_token_is_404(pool: PgPool) {
     let h = common::harness(pool);
@@ -581,3 +741,68 @@ async fn delete_unknown_token_is_404(pool: PgPool) {
         .unwrap();
     assert_eq!(resp.status(), StatusCode::NOT_FOUND);
 }
+
+/// Bot token names are user-supplied free-form strings; a 10 MB name
+/// was accepted before. Cap at 64 chars to match the other free-form
+/// identifier caps (tags, collection names). The response uses
+/// `ValidationFailed` (422 with per-field details) so clients can
+/// render the same shape they already handle for `attach_tag`.
+#[sqlx::test(migrations = "./migrations")]
+async fn create_token_rejects_name_over_64_chars(pool: PgPool) {
+    let h = common::harness(pool);
+    let (_, cookie) = common::register_user(&h.app).await;
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            "/api/v1/auth/tokens",
+            json!({ "name": "x".repeat(65) }),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::UNPROCESSABLE_ENTITY);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["error"]["code"], "validation_failed");
+    assert!(body["error"]["details"]["name"].is_string());
+}
+
+// ---- self-register toggle + /auth/config -----------------------------------
+
+#[sqlx::test(migrations = "./migrations")]
+async fn auth_config_reports_self_register_enabled_by_default(pool: PgPool) {
+    let h = common::harness(pool);
+    let resp = h
+        .app
+        .oneshot(common::get("/api/v1/auth/config"))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["self_register_enabled"], true);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn auth_config_reflects_self_register_disabled(pool: PgPool) {
+    let h = common::harness_with_self_register_disabled(pool);
+    let resp = h
+        .app
+        .oneshot(common::get("/api/v1/auth/config"))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["self_register_enabled"], false);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn register_returns_403_when_self_register_disabled(pool: PgPool) {
+    let h = common::harness_with_self_register_disabled(pool);
+    let resp = h
+        .app
+        .oneshot(common::post_json("/api/v1/auth/register", creds("alice")))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::FORBIDDEN);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["error"]["code"], "forbidden");
+}

backend/tests/api_mangas_cover.rs

@@ -410,3 +410,53 @@ async fn delete_cover_404_on_unknown_id(pool: PgPool) {
         .unwrap();
     assert_eq!(resp.status(), StatusCode::NOT_FOUND);
 }
+
+/// Authz: PUT /mangas/:id/cover must be uploader-only.
+#[sqlx::test(migrations = "./migrations")]
+async fn put_cover_forbidden_for_non_uploader(pool: PgPool) {
+    let h = harness(pool);
+    let (_, owner_cookie) = register_user(&h.app).await;
+    let (_, intruder_cookie) = register_user(&h.app).await;
+
+    let manga =
+        create_manga_with_cover(&h.app, &owner_cookie, "Mine", None).await;
+    let id = id_of(&manga);
+
+    let resp = h
+        .app
+        .oneshot(put_multipart_with_cookie(
+            &format!("/api/v1/mangas/{id}/cover"),
+            cover_form(&fake_png_bytes()),
+            &intruder_cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::FORBIDDEN);
+}
+
+/// Authz: DELETE /mangas/:id/cover must be uploader-only.
+#[sqlx::test(migrations = "./migrations")]
+async fn delete_cover_forbidden_for_non_uploader(pool: PgPool) {
+    let h = harness(pool);
+    let (_, owner_cookie) = register_user(&h.app).await;
+    let (_, intruder_cookie) = register_user(&h.app).await;
+
+    let manga = create_manga_with_cover(
+        &h.app,
+        &owner_cookie,
+        "Mine",
+        Some(("image/jpeg", &fake_jpeg_bytes())),
+    )
+    .await;
+    let id = id_of(&manga);
+
+    let resp = h
+        .app
+        .oneshot(delete_with_cookie(
+            &format!("/api/v1/mangas/{id}/cover"),
+            &intruder_cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::FORBIDDEN);
+}

backend/tests/api_mangas_metadata.rs

@@ -566,3 +566,78 @@ async fn patch_requires_authentication(pool: PgPool) {
         .unwrap();
     assert_eq!(resp.status(), StatusCode::UNAUTHORIZED);
 }
+
+/// A signed-in user who didn't upload the manga must not be able to
+/// PATCH it. Without the uploader-gate this returned 200 — see
+/// REVIEW.md "manga PATCH / cover endpoints don't check ownership".
+#[sqlx::test(migrations = "./migrations")]
+async fn patch_forbidden_for_non_uploader(pool: PgPool) {
+    let h = common::harness(pool);
+    let (_, owner_cookie) = common::register_user(&h.app).await;
+    let (_, intruder_cookie) = common::register_user(&h.app).await;
+
+    let created = create_manga(&h.app, &owner_cookie, json!({ "title": "Mine" })).await;
+    let id = id_of(&created);
+
+    let resp = h
+        .app
+        .oneshot(common::patch_json_with_cookie(
+            &format!("/api/v1/mangas/{id}"),
+            json!({ "status": "completed" }),
+            &intruder_cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::FORBIDDEN);
+}
+
+/// Owner can still edit their own manga (regression guard for the
+/// authz fix).
+#[sqlx::test(migrations = "./migrations")]
+async fn patch_allowed_for_uploader(pool: PgPool) {
+    let h = common::harness(pool);
+    let (_, cookie) = common::register_user(&h.app).await;
+    let created = create_manga(&h.app, &cookie, json!({ "title": "Owned" })).await;
+    let id = id_of(&created);
+    let resp = h
+        .app
+        .oneshot(common::patch_json_with_cookie(
+            &format!("/api/v1/mangas/{id}"),
+            json!({ "status": "completed" }),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+}
+
+/// Legacy rows with `uploaded_by IS NULL` (created before migration
+/// 0011) remain editable by any signed-in user. Without this carve-out
+/// the historical-data note in 0011 would be broken.
+#[sqlx::test(migrations = "./migrations")]
+async fn patch_allowed_on_legacy_null_uploader(pool: PgPool) {
+    let h = common::harness(pool.clone());
+    let (_, cookie) = common::register_user(&h.app).await;
+    let created = create_manga(&h.app, &cookie, json!({ "title": "Legacy" })).await;
+    let id = id_of(&created);
+
+    // Simulate a row uploaded before the column existed: clear
+    // uploaded_by directly via SQL.
+    sqlx::query("UPDATE mangas SET uploaded_by = NULL WHERE id = $1")
+        .bind(id)
+        .execute(&pool)
+        .await
+        .unwrap();
+
+    let (_, other_cookie) = common::register_user(&h.app).await;
+    let resp = h
+        .app
+        .oneshot(common::patch_json_with_cookie(
+            &format!("/api/v1/mangas/{id}"),
+            json!({ "status": "completed" }),
+            &other_cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+}

backend/tests/api_private_mode.rs

@@ -0,0 +1,189 @@
+//! Site-wide auth gate (`PRIVATE_MODE=true`).
+//!
+//! With private mode on, every API path except a small allowlist
+//! (`/health`, `/auth/config`, `/auth/login`, `/auth/logout`) requires
+//! a valid session cookie or bearer token, and `/auth/register` is
+//! force-blocked regardless of `ALLOW_SELF_REGISTER`. With private mode
+//! off (the default), nothing changes — the `public_mode_*` test
+//! pins that regression guard.
+
+mod common;
+
+use serde_json::json;
+use sqlx::PgPool;
+use tower::ServiceExt;
+
+use axum::http::StatusCode;
+
+#[sqlx::test(migrations = "./migrations")]
+async fn private_mode_blocks_anonymous_manga_list(pool: PgPool) {
+    let h = common::harness_with_private_mode(pool);
+    let resp = h.app.oneshot(common::get("/api/v1/mangas")).await.unwrap();
+    assert_eq!(resp.status(), StatusCode::UNAUTHORIZED);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn private_mode_blocks_anonymous_files(pool: PgPool) {
+    let h = common::harness_with_private_mode(pool);
+    // The path doesn't have to exist — the guard runs before routing,
+    // so the response is 401 (not 404). That's the property the test
+    // is pinning: nothing leaks via crafted URLs.
+    let resp = h
+        .app
+        .oneshot(common::get("/api/v1/files/anything.png"))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::UNAUTHORIZED);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn private_mode_allows_session_cookie_read(pool: PgPool) {
+    // Register through a non-private harness sharing the same DB pool
+    // so the session row exists. Then exercise the gate using a fresh
+    // private-mode harness against the same DB.
+    let public = common::harness(pool.clone());
+    let (_, cookie) = common::register_user(&public.app).await;
+
+    let private = common::harness_with_private_mode(pool);
+    let resp = private
+        .app
+        .oneshot(common::get_with_cookie("/api/v1/mangas", &cookie))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn private_mode_allows_bearer_token_read(pool: PgPool) {
+    let public = common::harness(pool.clone());
+    let (_, cookie) = common::register_user(&public.app).await;
+
+    let resp = public
+        .app
+        .clone()
+        .oneshot(common::post_json_with_cookie(
+            "/api/v1/auth/tokens",
+            json!({ "name": "private-mode-bot" }),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::CREATED);
+    let body = common::body_json(resp).await;
+    let bearer = body["bearer"].as_str().unwrap().to_string();
+
+    let private = common::harness_with_private_mode(pool);
+    let resp = private
+        .app
+        .oneshot(common::get_with_bearer("/api/v1/mangas", &bearer))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn private_mode_allows_login_endpoint_anonymous(pool: PgPool) {
+    // Seed a user via the public harness so login has credentials to
+    // verify against.
+    let public = common::harness(pool.clone());
+    let _ = public
+        .app
+        .clone()
+        .oneshot(common::post_json(
+            "/api/v1/auth/register",
+            json!({ "username": "alice", "password": "hunter2hunter2" }),
+        ))
+        .await
+        .unwrap();
+
+    let private = common::harness_with_private_mode(pool);
+    let resp = private
+        .app
+        .oneshot(common::post_json(
+            "/api/v1/auth/login",
+            json!({ "username": "alice", "password": "hunter2hunter2" }),
+        ))
+        .await
+        .unwrap();
+    // Reaches the login handler and succeeds — *not* 401 from the
+    // gate. That's the property we're pinning.
+    assert_eq!(resp.status(), StatusCode::OK);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn private_mode_allows_health_and_config_anonymous(pool: PgPool) {
+    let h = common::harness_with_private_mode(pool);
+
+    let r = h
+        .app
+        .clone()
+        .oneshot(common::get("/api/v1/health"))
+        .await
+        .unwrap();
+    assert_eq!(r.status(), StatusCode::OK);
+
+    let r = h
+        .app
+        .oneshot(common::get("/api/v1/auth/config"))
+        .await
+        .unwrap();
+    assert_eq!(r.status(), StatusCode::OK);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn private_mode_blocks_register_even_when_self_register_enabled(pool: PgPool) {
+    // harness_with_private_mode keeps `allow_self_register=true` (the
+    // default) — private mode is supposed to force-block register
+    // regardless. That's what this test pins.
+    let h = common::harness_with_private_mode(pool);
+    let resp = h
+        .app
+        .oneshot(common::post_json(
+            "/api/v1/auth/register",
+            json!({ "username": "alice", "password": "hunter2hunter2" }),
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::FORBIDDEN);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["error"]["code"], "forbidden");
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn auth_config_reports_private_mode_and_effective_self_register(pool: PgPool) {
+    let h = common::harness_with_private_mode(pool);
+    let resp = h
+        .app
+        .oneshot(common::get("/api/v1/auth/config"))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["private_mode"], true);
+    // Effective value: `allow_self_register && !private_mode` is false
+    // here even though the raw `allow_self_register` is true.
+    assert_eq!(body["self_register_enabled"], false);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn public_mode_does_not_gate_anonymous_reads(pool: PgPool) {
+    // Regression guard: with private_mode off (the default), the gate
+    // must be a no-op so existing public deployments stay public.
+    let h = common::harness(pool);
+    let resp = h.app.oneshot(common::get("/api/v1/mangas")).await.unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn public_mode_reports_private_mode_false(pool: PgPool) {
+    let h = common::harness(pool);
+    let resp = h
+        .app
+        .oneshot(common::get("/api/v1/auth/config"))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["private_mode"], false);
+    assert_eq!(body["self_register_enabled"], true);
+}

backend/tests/api_tags.rs

@@ -59,6 +59,31 @@ async fn reattach_same_tag_is_idempotent_and_returns_200(pool: PgPool) {
     assert_eq!(second.status(), StatusCode::OK);
 }
 
+/// Tag names over 64 chars are rejected at the handler boundary. The
+/// repo enforces the same cap, but doing it at the handler keeps the
+/// envelope consistent with the other validation paths
+/// (username, collection name, etc.).
+#[sqlx::test(migrations = "./migrations")]
+async fn attach_rejects_tag_name_over_64_chars(pool: PgPool) {
+    let h = common::harness(pool);
+    let (_, cookie) = common::register_user(&h.app).await;
+    let manga_id = common::seed_manga_via_api(&h.app, &cookie, "Berserk").await;
+
+    let long_name: String = "x".repeat(65);
+    let resp = h
+        .app
+        .oneshot(common::post_json_with_cookie(
+            &format!("/api/v1/mangas/{manga_id}/tags"),
+            json!({ "name": long_name }),
+            &cookie,
+        ))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::UNPROCESSABLE_ENTITY);
+    let body = common::body_json(resp).await;
+    assert_eq!(body["error"]["code"], "validation_failed");
+}
+
 #[sqlx::test(migrations = "./migrations")]
 async fn tag_names_dedup_case_insensitively(pool: PgPool) {
     let h = common::harness(pool);

backend/tests/common/mod.rs

@@ -15,6 +15,7 @@ use tempfile::TempDir;
 use tower::ServiceExt;
 
 use mangalord::app::{router, AppState};
+use mangalord::auth::rate_limit::AuthRateLimiter;
 use mangalord::config::{AuthConfig, UploadConfig};
 use mangalord::storage::{LocalStorage, Storage, StorageError, StreamingFile};
 
@@ -49,20 +50,115 @@ fn harness_inner(
     storage: Arc<dyn Storage>,
     storage_dir: TempDir,
 ) -> Harness {
+    harness_with_auth_config(pool, storage, storage_dir, AuthConfig {
+        cookie_secure: false,
+        ..AuthConfig::default()
+    })
+}
+
+fn harness_with_auth_config(
+    pool: PgPool,
+    storage: Arc<dyn Storage>,
+    storage_dir: TempDir,
+    auth: AuthConfig,
+) -> Harness {
+    let auth_limiter = Arc::new(AuthRateLimiter::new(auth.rate_limit));
     let state = AppState {
         db: pool,
         storage,
-        auth: AuthConfig { cookie_secure: false, ..AuthConfig::default() },
+        auth,
         upload: UploadConfig {
             // Keep file caps small in tests so the size-cap path is cheap to
             // exercise without producing tens of MBs of bytes.
             max_request_bytes: 4 * 1024 * 1024,
             max_file_bytes: 256 * 1024,
         },
+        auth_limiter,
+        // Default harness has no crawler daemon wired up; admin resync
+        // handlers return 503 in this config. Tests that need a stub
+        // resync service swap it in via `harness_with_resync`.
+        resync: None,
     };
     Harness { app: router(state), _storage_dir: storage_dir }
 }
 
+/// Like [`harness`] but flips `ALLOW_SELF_REGISTER` off so the
+/// register-disabled test exercises the 403 branch in
+/// `api::auth::register`.
+pub fn harness_with_self_register_disabled(pool: PgPool) -> Harness {
+    let storage_dir = tempfile::tempdir().expect("tempdir");
+    let storage = Arc::new(LocalStorage::new(storage_dir.path()));
+    let auth = AuthConfig {
+        cookie_secure: false,
+        allow_self_register: false,
+        ..AuthConfig::default()
+    };
+    harness_with_auth_config(pool, storage, storage_dir, auth)
+}
+
+/// Like [`harness`] but flips `PRIVATE_MODE` on so the site-wide auth
+/// gate is exercised. `allow_self_register` stays at its default `true`
+/// to verify that private mode force-disables self-registration on top
+/// of whatever `ALLOW_SELF_REGISTER` says.
+pub fn harness_with_private_mode(pool: PgPool) -> Harness {
+    let storage_dir = tempfile::tempdir().expect("tempdir");
+    let storage = Arc::new(LocalStorage::new(storage_dir.path()));
+    let auth = AuthConfig {
+        cookie_secure: false,
+        private_mode: true,
+        ..AuthConfig::default()
+    };
+    harness_with_auth_config(pool, storage, storage_dir, auth)
+}
+
+/// Like [`harness`] but configures a tight auth rate limit. Used by
+/// the brute-force-rate-limiting test.
+pub fn harness_with_auth_rate_limit(
+    pool: PgPool,
+    per_sec: u32,
+    burst: u32,
+) -> Harness {
+    let storage_dir = tempfile::tempdir().expect("tempdir");
+    let storage = Arc::new(LocalStorage::new(storage_dir.path()));
+    let auth = AuthConfig {
+        cookie_secure: false,
+        rate_limit: mangalord::auth::rate_limit::RateLimitConfig { per_sec, burst },
+        ..AuthConfig::default()
+    };
+    harness_with_auth_config(pool, storage, storage_dir, auth)
+}
+
+/// Like [`harness`] but slots a caller-supplied [`ResyncService`] stub
+/// into `AppState.resync`. Used by the admin resync tests so the
+/// endpoint path is exercised without standing up a real Chromium.
+pub fn harness_with_resync(
+    pool: PgPool,
+    resync: Arc<dyn mangalord::crawler::resync::ResyncService>,
+) -> Harness {
+    let storage_dir = tempfile::tempdir().expect("tempdir");
+    let storage = Arc::new(LocalStorage::new(storage_dir.path()));
+    let auth = AuthConfig {
+        cookie_secure: false,
+        ..AuthConfig::default()
+    };
+    let auth_limiter = Arc::new(AuthRateLimiter::new(auth.rate_limit));
+    let state = AppState {
+        db: pool,
+        storage,
+        auth,
+        upload: UploadConfig {
+            max_request_bytes: 4 * 1024 * 1024,
+            max_file_bytes: 256 * 1024,
+        },
+        auth_limiter,
+        resync: Some(resync),
+    };
+    Harness {
+        app: router(state),
+        _storage_dir: storage_dir,
+    }
+}
+
 /// Wraps a real `Storage` and fails on the N-th `put` call so tests can
 /// assert that handlers roll their DB writes back when storage errors
 /// mid-upload. Reads and other operations delegate to `inner`.

backend/tests/crawler_browser_smoke.rs

@@ -10,6 +10,11 @@
 //!
 //! Override the cache location with `CRAWLER_CHROMIUM_DIR=/some/path` if
 //! `$HOME/.cache/mangalord/chromium` isn't writable.
+//!
+//! Set `CRAWLER_CHROMIUM_BINARY=/usr/bin/chromium-headless-shell` (or
+//! another system chromium path) to exercise the system-chromium
+//! launch path instead of the fetcher download — this is the path the
+//! Raspberry Pi deployment takes.
 
 use mangalord::crawler::browser::{self, LaunchOptions};
 

backend/tests/crawler_daemon.rs

@@ -370,3 +370,279 @@ async fn enqueue_bookmarked_pending_skips_dropped_sources(pool: PgPool) {
     );
 }
 
+#[sqlx::test(migrations = "./migrations")]
+async fn enqueue_bookmarked_pending_skips_recently_dead_chapters(pool: PgPool) {
+    // Setup: a chapter whose last SyncChapterContent job died yesterday.
+    // The cron tick must not re-enqueue — without the quarantine, the
+    // chapter would spin: re-enqueue → max_attempts retries → dies again
+    // → re-enqueue next tick → forever.
+    let user_id: Uuid = sqlx::query_scalar(
+        "INSERT INTO users (username, password_hash) VALUES ($1, $2) RETURNING id",
+    )
+    .bind("alice")
+    .bind("not-a-real-hash")
+    .fetch_one(&pool)
+    .await
+    .unwrap();
+    let manga_id: Uuid =
+        sqlx::query_scalar("INSERT INTO mangas (title) VALUES ($1) RETURNING id")
+            .bind("Test")
+            .fetch_one(&pool)
+            .await
+            .unwrap();
+    sqlx::query(
+        "INSERT INTO sources (id, name, base_url) VALUES ($1, $2, $3) ON CONFLICT DO NOTHING",
+    )
+    .bind("target")
+    .bind("Target")
+    .bind("https://example.com")
+    .execute(&pool)
+    .await
+    .unwrap();
+    let chapter_id: Uuid = sqlx::query_scalar(
+        "INSERT INTO chapters (manga_id, number, page_count) VALUES ($1, 1, 0) RETURNING id",
+    )
+    .bind(manga_id)
+    .fetch_one(&pool)
+    .await
+    .unwrap();
+    sqlx::query(
+        "INSERT INTO chapter_sources (source_id, source_chapter_key, chapter_id, source_url) \
+         VALUES ($1, $2, $3, $4)",
+    )
+    .bind("target")
+    .bind("ch1")
+    .bind(chapter_id)
+    .bind("https://example.com/ch1")
+    .execute(&pool)
+    .await
+    .unwrap();
+    sqlx::query("INSERT INTO bookmarks (user_id, manga_id) VALUES ($1, $2)")
+        .bind(user_id)
+        .bind(manga_id)
+        .execute(&pool)
+        .await
+        .unwrap();
+    // The dead job from the prior tick, updated 1 day ago (well inside the
+    // 7-day quarantine window).
+    sqlx::query(
+        "INSERT INTO crawler_jobs (payload, state, updated_at) \
+         VALUES ($1::jsonb, 'dead', now() - interval '1 day')",
+    )
+    .bind(serde_json::json!({
+        "kind": "sync_chapter_content",
+        "source_id": "target",
+        "chapter_id": chapter_id.to_string(),
+        "source_chapter_key": "ch1",
+    }))
+    .execute(&pool)
+    .await
+    .unwrap();
+
+    let summary = pipeline::enqueue_bookmarked_pending(&pool).await.unwrap();
+    assert_eq!(summary.inserted, 0, "recently dead chapter is quarantined");
+    assert_eq!(summary.skipped, 0);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn enqueue_bookmarked_pending_resumes_after_quarantine_expires(pool: PgPool) {
+    // Same setup as above but the dead job is 10 days old — past the
+    // 7-day quarantine. The chapter should be re-enqueued so a once-failed
+    // chapter eventually gets a second shot at success.
+    let user_id: Uuid = sqlx::query_scalar(
+        "INSERT INTO users (username, password_hash) VALUES ($1, $2) RETURNING id",
+    )
+    .bind("alice")
+    .bind("not-a-real-hash")
+    .fetch_one(&pool)
+    .await
+    .unwrap();
+    let manga_id: Uuid =
+        sqlx::query_scalar("INSERT INTO mangas (title) VALUES ($1) RETURNING id")
+            .bind("Test")
+            .fetch_one(&pool)
+            .await
+            .unwrap();
+    sqlx::query(
+        "INSERT INTO sources (id, name, base_url) VALUES ($1, $2, $3) ON CONFLICT DO NOTHING",
+    )
+    .bind("target")
+    .bind("Target")
+    .bind("https://example.com")
+    .execute(&pool)
+    .await
+    .unwrap();
+    let chapter_id: Uuid = sqlx::query_scalar(
+        "INSERT INTO chapters (manga_id, number, page_count) VALUES ($1, 1, 0) RETURNING id",
+    )
+    .bind(manga_id)
+    .fetch_one(&pool)
+    .await
+    .unwrap();
+    sqlx::query(
+        "INSERT INTO chapter_sources (source_id, source_chapter_key, chapter_id, source_url) \
+         VALUES ($1, $2, $3, $4)",
+    )
+    .bind("target")
+    .bind("ch1")
+    .bind(chapter_id)
+    .bind("https://example.com/ch1")
+    .execute(&pool)
+    .await
+    .unwrap();
+    sqlx::query("INSERT INTO bookmarks (user_id, manga_id) VALUES ($1, $2)")
+        .bind(user_id)
+        .bind(manga_id)
+        .execute(&pool)
+        .await
+        .unwrap();
+    sqlx::query(
+        "INSERT INTO crawler_jobs (payload, state, updated_at) \
+         VALUES ($1::jsonb, 'dead', now() - interval '10 days')",
+    )
+    .bind(serde_json::json!({
+        "kind": "sync_chapter_content",
+        "source_id": "target",
+        "chapter_id": chapter_id.to_string(),
+        "source_chapter_key": "ch1",
+    }))
+    .execute(&pool)
+    .await
+    .unwrap();
+
+    let summary = pipeline::enqueue_bookmarked_pending(&pool).await.unwrap();
+    assert_eq!(
+        summary.inserted, 1,
+        "dead chapter is re-enqueued after quarantine expires"
+    );
+}
+
+/// Helper: insert a chapter with the given `number` and a non-dropped
+/// source row, returning the chapter id. Used by the ordering tests so
+/// the setup boilerplate doesn't drown the assertion.
+async fn insert_pending_chapter(
+    pool: &PgPool,
+    manga_id: Uuid,
+    number: i32,
+    source_chapter_key: &str,
+) -> Uuid {
+    let chapter_id: Uuid = sqlx::query_scalar(
+        "INSERT INTO chapters (manga_id, number, page_count) VALUES ($1, $2, 0) RETURNING id",
+    )
+    .bind(manga_id)
+    .bind(number)
+    .fetch_one(pool)
+    .await
+    .unwrap();
+    sqlx::query(
+        "INSERT INTO chapter_sources (source_id, source_chapter_key, chapter_id, source_url) \
+         VALUES ($1, $2, $3, $4)",
+    )
+    .bind("target")
+    .bind(source_chapter_key)
+    .bind(chapter_id)
+    .bind(format!("https://example.com/{source_chapter_key}"))
+    .execute(pool)
+    .await
+    .unwrap();
+    chapter_id
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn enqueue_bookmarked_pending_queues_chapters_in_ascending_number_order(pool: PgPool) {
+    // Insert chapters with `number` values 3, 1, 2 in that insertion
+    // order — so `created_at` order (the previous tiebreaker) does NOT
+    // match number order. After enqueue + lease, the worker should see
+    // chapters 1, 2, 3 in that sequence.
+    let user_id: Uuid = sqlx::query_scalar(
+        "INSERT INTO users (username, password_hash) VALUES ($1, $2) RETURNING id",
+    )
+    .bind("alice")
+    .bind("not-a-real-hash")
+    .fetch_one(&pool)
+    .await
+    .unwrap();
+    let manga_id: Uuid = sqlx::query_scalar("INSERT INTO mangas (title) VALUES ($1) RETURNING id")
+        .bind("Test")
+        .fetch_one(&pool)
+        .await
+        .unwrap();
+    sqlx::query(
+        "INSERT INTO sources (id, name, base_url) VALUES ($1, $2, $3) ON CONFLICT DO NOTHING",
+    )
+    .bind("target")
+    .bind("Target")
+    .bind("https://example.com")
+    .execute(&pool)
+    .await
+    .unwrap();
+    let c3 = insert_pending_chapter(&pool, manga_id, 3, "ch3").await;
+    let c1 = insert_pending_chapter(&pool, manga_id, 1, "ch1").await;
+    let c2 = insert_pending_chapter(&pool, manga_id, 2, "ch2").await;
+    sqlx::query("INSERT INTO bookmarks (user_id, manga_id) VALUES ($1, $2)")
+        .bind(user_id)
+        .bind(manga_id)
+        .execute(&pool)
+        .await
+        .unwrap();
+
+    let summary = pipeline::enqueue_bookmarked_pending(&pool).await.unwrap();
+    assert_eq!(summary.inserted, 3);
+
+    let leases = jobs::lease(&pool, None, 10, std::time::Duration::from_secs(60))
+        .await
+        .unwrap();
+    let leased_chapter_ids: Vec<Uuid> = leases
+        .iter()
+        .map(|l| match &l.payload {
+            JobPayload::SyncChapterContent { chapter_id, .. } => *chapter_id,
+            other => panic!("unexpected payload kind: {other:?}"),
+        })
+        .collect();
+    assert_eq!(
+        leased_chapter_ids,
+        vec![c1, c2, c3],
+        "chapters must be leased in ascending chapter-number order, not insertion order"
+    );
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn enqueue_pending_for_manga_queues_chapters_in_ascending_number_order(pool: PgPool) {
+    // Same scenario as above but exercising the bookmark-create hook path
+    // (`enqueue_pending_for_manga`) which has its own ORDER BY.
+    let manga_id: Uuid = sqlx::query_scalar("INSERT INTO mangas (title) VALUES ($1) RETURNING id")
+        .bind("Test")
+        .fetch_one(&pool)
+        .await
+        .unwrap();
+    sqlx::query(
+        "INSERT INTO sources (id, name, base_url) VALUES ($1, $2, $3) ON CONFLICT DO NOTHING",
+    )
+    .bind("target")
+    .bind("Target")
+    .bind("https://example.com")
+    .execute(&pool)
+    .await
+    .unwrap();
+    let c3 = insert_pending_chapter(&pool, manga_id, 3, "ch3").await;
+    let c1 = insert_pending_chapter(&pool, manga_id, 1, "ch1").await;
+    let c2 = insert_pending_chapter(&pool, manga_id, 2, "ch2").await;
+
+    let summary = pipeline::enqueue_pending_for_manga(&pool, manga_id)
+        .await
+        .unwrap();
+    assert_eq!(summary.inserted, 3);
+
+    let leases = jobs::lease(&pool, None, 10, std::time::Duration::from_secs(60))
+        .await
+        .unwrap();
+    let leased_chapter_ids: Vec<Uuid> = leases
+        .iter()
+        .map(|l| match &l.payload {
+            JobPayload::SyncChapterContent { chapter_id, .. } => *chapter_id,
+            other => panic!("unexpected payload kind: {other:?}"),
+        })
+        .collect();
+    assert_eq!(leased_chapter_ids, vec![c1, c2, c3]);
+}
+

backend/tests/crawler_incremental.rs

@@ -1,85 +0,0 @@
-//! Integration tests for the incremental-mode coordination state:
-//! `mark_seed_completed` / `seed_completed_at` round-trip via the
-//! `crawler_state` table.
-//!
-//! End-to-end pipeline behavior (walker + stop-on-Unchanged) requires
-//! a real `chromiumoxide::Browser` to construct a `FetchContext`, so
-//! the live integration of that path is covered by
-//! `crawler_browser_smoke.rs` instead. The pure stop logic itself is
-//! unit-tested in `crawler::pipeline::tests`.
-
-use chrono::Utc;
-use mangalord::repo::crawler;
-use sqlx::PgPool;
-
-#[sqlx::test(migrations = "./migrations")]
-async fn seed_completed_at_none_before_any_run(pool: PgPool) {
-    crawler::ensure_source(&pool, "target", "T", "https://x.example")
-        .await
-        .unwrap();
-    let res = crawler::seed_completed_at(&pool, "target").await.unwrap();
-    assert!(res.is_none(), "fresh source has no seed marker");
-}
-
-#[sqlx::test(migrations = "./migrations")]
-async fn mark_seed_completed_then_read_round_trips_timestamp(pool: PgPool) {
-    crawler::ensure_source(&pool, "target", "T", "https://x.example")
-        .await
-        .unwrap();
-    let at = Utc::now();
-    crawler::mark_seed_completed(&pool, "target", at)
-        .await
-        .unwrap();
-    let read = crawler::seed_completed_at(&pool, "target")
-        .await
-        .unwrap()
-        .expect("marker present after mark");
-    // RFC3339 round-trip is millisecond-precise on chrono::Utc; allow a
-    // 1ms tolerance to absorb postgres jsonb whitespace canonicalization.
-    let drift = (read - at).num_milliseconds().abs();
-    assert!(drift <= 1, "round-trip drift: {drift}ms (at={at}, read={read})");
-}
-
-#[sqlx::test(migrations = "./migrations")]
-async fn mark_seed_completed_overwrites_previous_value(pool: PgPool) {
-    crawler::ensure_source(&pool, "target", "T", "https://x.example")
-        .await
-        .unwrap();
-    let first = Utc::now() - chrono::Duration::hours(1);
-    let second = Utc::now();
-    crawler::mark_seed_completed(&pool, "target", first)
-        .await
-        .unwrap();
-    crawler::mark_seed_completed(&pool, "target", second)
-        .await
-        .unwrap();
-    let read = crawler::seed_completed_at(&pool, "target")
-        .await
-        .unwrap()
-        .expect("marker present");
-    let drift = (read - second).num_milliseconds().abs();
-    assert!(drift <= 1, "should reflect the latest mark, not the first");
-}
-
-#[sqlx::test(migrations = "./migrations")]
-async fn seed_completed_is_per_source(pool: PgPool) {
-    // Two sources, only one is marked complete. The other must still
-    // report None — the key is namespaced by source_id.
-    crawler::ensure_source(&pool, "target", "T", "https://x.example")
-        .await
-        .unwrap();
-    crawler::ensure_source(&pool, "other", "O", "https://y.example")
-        .await
-        .unwrap();
-    crawler::mark_seed_completed(&pool, "target", Utc::now())
-        .await
-        .unwrap();
-    assert!(crawler::seed_completed_at(&pool, "target")
-        .await
-        .unwrap()
-        .is_some());
-    assert!(crawler::seed_completed_at(&pool, "other")
-        .await
-        .unwrap()
-        .is_none());
-}

backend/tests/crawler_jobs.rs

@@ -9,7 +9,6 @@ use std::time::Duration;
 use mangalord::crawler::jobs::{
     self, EnqueueResult, JobPayload, KIND_SYNC_CHAPTER_CONTENT,
 };
-use mangalord::crawler::source::DiscoverMode;
 use sqlx::PgPool;
 use uuid::Uuid;
 
@@ -21,10 +20,13 @@ fn chapter_content_payload(chapter_id: Uuid) -> JobPayload {
     }
 }
 
-fn discover_payload() -> JobPayload {
-    JobPayload::Discover {
+/// A non-`SyncChapterContent` payload, used to assert that only the
+/// chapter-content kind is deduplicated by the partial index and that
+/// `lease`'s kind filter correctly excludes other kinds.
+fn sync_manga_payload(key: &str) -> JobPayload {
+    JobPayload::SyncManga {
         source_id: "target".into(),
-        mode: DiscoverMode::Backfill,
+        source_manga_key: key.into(),
     }
 }
 
@@ -141,7 +143,7 @@ async fn different_chapter_ids_can_coexist(pool: PgPool) {
 
 #[sqlx::test(migrations = "./migrations")]
 async fn non_chapter_content_payloads_are_never_deduped(pool: PgPool) {
-    let p = discover_payload();
+    let p = sync_manga_payload("foo");
     assert!(matches!(
         jobs::enqueue(&pool, &p).await.unwrap(),
         EnqueueResult::Inserted(_)
@@ -185,7 +187,10 @@ async fn lease_marks_running_and_bumps_attempts_and_sets_leased_until(pool: PgPo
 
 #[sqlx::test(migrations = "./migrations")]
 async fn lease_with_kind_filter_only_matches_that_kind(pool: PgPool) {
-    let discover_id = match jobs::enqueue(&pool, &discover_payload()).await.unwrap() {
+    let manga_id = match jobs::enqueue(&pool, &sync_manga_payload("foo"))
+        .await
+        .unwrap()
+    {
         EnqueueResult::Inserted(id) => id,
         _ => unreachable!(),
     };
@@ -207,8 +212,8 @@ async fn lease_with_kind_filter_only_matches_that_kind(pool: PgPool) {
     .unwrap();
     assert_eq!(leases.len(), 1, "only chapter content payload leases");
     assert_eq!(leases[0].id, chapter_id);
-    // discover is still pending
-    assert_eq!(job_state(&pool, discover_id).await, "pending");
+    // sync_manga is still pending
+    assert_eq!(job_state(&pool, manga_id).await, "pending");
 }
 
 #[sqlx::test(migrations = "./migrations")]
@@ -355,6 +360,112 @@ async fn ack_failed_at_max_marks_dead(pool: PgPool) {
     assert_eq!(last_error.as_deref(), Some("final boom"));
 }
 
+#[sqlx::test(migrations = "./migrations")]
+async fn ack_done_no_ops_when_lease_was_stolen(pool: PgPool) {
+    // Worker A's lease expires, worker B re-leases the job (state stays
+    // 'running' but attempts++ and leased_until refreshed). A late
+    // ack_done from worker A must not clobber B's progress.
+    let id = match jobs::enqueue(&pool, &chapter_content_payload(Uuid::new_v4()))
+        .await
+        .unwrap()
+    {
+        EnqueueResult::Inserted(id) => id,
+        _ => unreachable!(),
+    };
+    // Worker A grabs the lease, but its lease expires immediately.
+    let _a_leases = jobs::lease(&pool, None, 1, Duration::from_secs(60))
+        .await
+        .unwrap();
+    sqlx::query("UPDATE crawler_jobs SET leased_until = now() - interval '1 minute' WHERE id = $1")
+        .bind(id)
+        .execute(&pool)
+        .await
+        .unwrap();
+    // Worker B re-leases the expired-but-still-running job.
+    let b_leases = jobs::lease(&pool, None, 1, Duration::from_secs(60))
+        .await
+        .unwrap();
+    assert_eq!(b_leases.len(), 1);
+    assert_eq!(b_leases[0].attempts, 2, "re-lease bumps attempts");
+
+    // Worker A's late ack_done — guarded by `state = 'running'` + lease_id
+    // but in the simplest implementation the guard is state-only. Either
+    // way, the job stays 'running' with worker B's progress intact.
+    jobs::ack_done(&pool, id).await.unwrap();
+    // Worker B is still working; until B acks, the job remains 'running'
+    // with its leased_until in the future and attempts == 2.
+    // (We can't make ack_done's lease_id distinguish A from B today —
+    // both share the same `id` — so the strongest current guarantee is
+    // that a late ack_done doesn't fire when state is already 'done',
+    // exercised below.)
+    // Finalize: worker B acks done.
+    jobs::ack_done(&pool, b_leases[0].id).await.unwrap();
+    assert_eq!(job_state(&pool, id).await, "done");
+    assert_eq!(job_attempts(&pool, id).await, 2);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn ack_failed_no_ops_when_state_is_not_running(pool: PgPool) {
+    // After a job transitions to 'done', a stale ack_failed (e.g. a
+    // worker that finished work and queued its ack but then handed off
+    // before the SQL ran) must not flip the state back to 'pending' or
+    // 'dead'. The `state = 'running'` predicate enforces this.
+    let id = match jobs::enqueue(&pool, &chapter_content_payload(Uuid::new_v4()))
+        .await
+        .unwrap()
+    {
+        EnqueueResult::Inserted(id) => id,
+        _ => unreachable!(),
+    };
+    let leases = jobs::lease(&pool, None, 1, Duration::from_secs(60))
+        .await
+        .unwrap();
+    jobs::ack_done(&pool, leases[0].id).await.unwrap();
+    assert_eq!(job_state(&pool, id).await, "done");
+
+    // Late ack_failed arrives. Must be a no-op.
+    jobs::ack_failed(&pool, leases[0].id, "late", 1, 5)
+        .await
+        .unwrap();
+    assert_eq!(
+        job_state(&pool, id).await,
+        "done",
+        "late ack_failed must not resurrect a done job"
+    );
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn release_no_ops_when_state_is_not_running(pool: PgPool) {
+    // Mirror of ack_failed_no_ops_when_state_is_not_running. release also
+    // decrements `attempts`, which would corrupt a re-leased job's
+    // attempt count if the guard were missing.
+    let id = match jobs::enqueue(&pool, &chapter_content_payload(Uuid::new_v4()))
+        .await
+        .unwrap()
+    {
+        EnqueueResult::Inserted(id) => id,
+        _ => unreachable!(),
+    };
+    let leases = jobs::lease(&pool, None, 1, Duration::from_secs(60))
+        .await
+        .unwrap();
+    jobs::ack_done(&pool, leases[0].id).await.unwrap();
+    let attempts_before = job_attempts(&pool, id).await;
+
+    // Late release arrives.
+    jobs::release(&pool, leases[0].id).await.unwrap();
+    assert_eq!(
+        job_state(&pool, id).await,
+        "done",
+        "late release must not flip a done job back to pending"
+    );
+    assert_eq!(
+        job_attempts(&pool, id).await,
+        attempts_before,
+        "late release must not decrement attempts of a non-running job"
+    );
+}
+
 #[sqlx::test(migrations = "./migrations")]
 async fn release_returns_to_pending_and_undoes_attempt_increment(pool: PgPool) {
     let id = match jobs::enqueue(&pool, &chapter_content_payload(Uuid::new_v4()))
@@ -420,6 +531,89 @@ async fn reap_done_deletes_old_rows_keeps_fresh(pool: PgPool) {
     assert_eq!(remaining, vec![fresh_id], "only fresh row remains");
 }
 
+#[sqlx::test(migrations = "./migrations")]
+async fn lease_ties_on_scheduled_at_break_by_created_at(pool: PgPool) {
+    // Locks in the tiebreaker that lets enqueue order survive the lease
+    // step: when many jobs share `scheduled_at` (the common cron-batch
+    // case), the worker must pick the earliest-inserted row, not whatever
+    // Postgres returns in heap order. The enqueue path inserts chapters
+    // in chapter-number order, so this tiebreaker is what makes "queue
+    // in rising order" observable at the dequeue side too.
+    let a = match jobs::enqueue(&pool, &chapter_content_payload(Uuid::new_v4()))
+        .await
+        .unwrap()
+    {
+        EnqueueResult::Inserted(id) => id,
+        _ => unreachable!(),
+    };
+    let b = match jobs::enqueue(&pool, &chapter_content_payload(Uuid::new_v4()))
+        .await
+        .unwrap()
+    {
+        EnqueueResult::Inserted(id) => id,
+        _ => unreachable!(),
+    };
+    let c = match jobs::enqueue(&pool, &chapter_content_payload(Uuid::new_v4()))
+        .await
+        .unwrap()
+    {
+        EnqueueResult::Inserted(id) => id,
+        _ => unreachable!(),
+    };
+
+    // Pin `scheduled_at` to a single literal instant (shared across all
+    // three rows — `now()` would yield a different microsecond per UPDATE
+    // and make scheduled_at the actual sort key). Reverse `created_at`
+    // against insertion order so heap order would give the wrong answer.
+    let shared_scheduled = chrono::Utc::now() - chrono::Duration::hours(1);
+    sqlx::query(
+        "UPDATE crawler_jobs \
+            SET scheduled_at = $2, \
+                created_at   = $3 \
+          WHERE id = $1",
+    )
+    .bind(a)
+    .bind(shared_scheduled)
+    .bind(chrono::Utc::now() - chrono::Duration::seconds(10))
+    .execute(&pool)
+    .await
+    .unwrap();
+    sqlx::query(
+        "UPDATE crawler_jobs \
+            SET scheduled_at = $2, \
+                created_at   = $3 \
+          WHERE id = $1",
+    )
+    .bind(b)
+    .bind(shared_scheduled)
+    .bind(chrono::Utc::now() - chrono::Duration::seconds(20))
+    .execute(&pool)
+    .await
+    .unwrap();
+    sqlx::query(
+        "UPDATE crawler_jobs \
+            SET scheduled_at = $2, \
+                created_at   = $3 \
+          WHERE id = $1",
+    )
+    .bind(c)
+    .bind(shared_scheduled)
+    .bind(chrono::Utc::now() - chrono::Duration::seconds(30))
+    .execute(&pool)
+    .await
+    .unwrap();
+
+    let leases = jobs::lease(&pool, None, 10, Duration::from_secs(60))
+        .await
+        .unwrap();
+    let order: Vec<Uuid> = leases.iter().map(|l| l.id).collect();
+    assert_eq!(
+        order,
+        vec![c, b, a],
+        "lease must return jobs in created_at order when scheduled_at ties"
+    );
+}
+
 #[sqlx::test(migrations = "./migrations")]
 async fn reap_done_zero_is_a_no_op(pool: PgPool) {
     let id = match jobs::enqueue(&pool, &chapter_content_payload(Uuid::new_v4()))

backend/tests/crawler_recovery_flag.rs

@@ -0,0 +1,82 @@
+//! Integration tests for the per-source recovery flag:
+//! `mark_run_started` / `mark_run_completed` / `last_run_completed_cleanly`
+//! round-trip via the `crawler_state` table.
+//!
+//! End-to-end pipeline behavior (a crashed run forcing a recovery sweep
+//! on the next tick) requires a real `chromiumoxide::Browser` to drive
+//! the walker, so that path is covered by `crawler_browser_smoke.rs`.
+//! The pure stop-condition logic itself is unit-tested in
+//! `crawler::pipeline::tests`.
+
+use mangalord::repo::crawler;
+use sqlx::PgPool;
+
+#[sqlx::test(migrations = "./migrations")]
+async fn defaults_to_clean_when_no_marker(pool: PgPool) {
+    // First-ever run semantics: absence of the key must NOT trigger a
+    // recovery walk on a virgin DB. Treat missing as "previous run
+    // completed cleanly" so the first tick can take the early-stop path.
+    crawler::ensure_source(&pool, "target", "T", "https://x.example")
+        .await
+        .unwrap();
+    let clean = crawler::last_run_completed_cleanly(&pool, "target")
+        .await
+        .unwrap();
+    assert!(clean, "absent marker must read as clean");
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn mark_run_started_flips_to_false(pool: PgPool) {
+    crawler::ensure_source(&pool, "target", "T", "https://x.example")
+        .await
+        .unwrap();
+    crawler::mark_run_started(&pool, "target").await.unwrap();
+    let clean = crawler::last_run_completed_cleanly(&pool, "target")
+        .await
+        .unwrap();
+    assert!(!clean, "after mark_run_started, flag must read false");
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn started_then_completed_round_trips_to_clean(pool: PgPool) {
+    // Steady-state: a run starts (flag → false) and exits cleanly
+    // (flag → true). The next tick should see "clean" and apply the
+    // normal stop condition.
+    crawler::ensure_source(&pool, "target", "T", "https://x.example")
+        .await
+        .unwrap();
+    crawler::mark_run_started(&pool, "target").await.unwrap();
+    crawler::mark_run_completed(&pool, "target").await.unwrap();
+    let clean = crawler::last_run_completed_cleanly(&pool, "target")
+        .await
+        .unwrap();
+    assert!(
+        clean,
+        "after start → complete the flag must round-trip to clean"
+    );
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn flag_is_per_source(pool: PgPool) {
+    // Two sources, only one is mid-run. The other must still report
+    // clean — the crawler_state key is namespaced by source_id.
+    crawler::ensure_source(&pool, "target", "T", "https://x.example")
+        .await
+        .unwrap();
+    crawler::ensure_source(&pool, "other", "O", "https://y.example")
+        .await
+        .unwrap();
+    crawler::mark_run_started(&pool, "target").await.unwrap();
+    assert!(
+        !crawler::last_run_completed_cleanly(&pool, "target")
+            .await
+            .unwrap(),
+        "target is mid-run"
+    );
+    assert!(
+        crawler::last_run_completed_cleanly(&pool, "other")
+            .await
+            .unwrap(),
+        "other source is untouched and reads clean"
+    );
+}

backend/tests/crawler_sync.rs

@@ -6,6 +6,7 @@
 
 use mangalord::crawler::source::{SourceChapterRef, SourceManga};
 use mangalord::repo::crawler::{self, ChapterDiff, UpsertStatus};
+use mangalord::repo::chapter as chapter_repo;
 use sqlx::PgPool;
 use uuid::Uuid;
 
@@ -232,6 +233,67 @@ async fn sync_chapters_adds_new_refreshes_existing_and_drops_vanished(pool: PgPo
     assert!(dropped.0.is_some(), "ch2 should be soft-dropped");
 }
 
+#[sqlx::test(migrations = "./migrations")]
+async fn live_chapter_count_returns_zero_for_unknown_source_key(pool: PgPool) {
+    crawler::ensure_source(&pool, "target", "T", "https://x.example")
+        .await
+        .unwrap();
+    // No manga_sources row yet → unknown key path. Must not error and
+    // must report zero so the partial-render guard accepts the
+    // "brand-new manga with no chapters" case as legitimate.
+    let n = crawler::live_chapter_count_for_source_manga(&pool, "target", "nobody")
+        .await
+        .unwrap();
+    assert_eq!(n, 0);
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn live_chapter_count_only_counts_live_sources(pool: PgPool) {
+    crawler::ensure_source(&pool, "target", "T", "https://x.example")
+        .await
+        .unwrap();
+    let m = sample_manga("foo", "Foo Manga", "hash-1");
+    let up = crawler::upsert_manga_from_source(&pool, "target", "https://x.example/foo", &m)
+        .await
+        .unwrap();
+    let chapters = vec![
+        SourceChapterRef {
+            source_chapter_key: "1".into(),
+            number: 1,
+            title: Some("Ch.1".into()),
+            url: "https://x.example/foo/1".into(),
+        },
+        SourceChapterRef {
+            source_chapter_key: "2".into(),
+            number: 2,
+            title: Some("Ch.2".into()),
+            url: "https://x.example/foo/2".into(),
+        },
+    ];
+    crawler::sync_manga_chapters(&pool, "target", up.manga_id, &chapters)
+        .await
+        .unwrap();
+    assert_eq!(
+        crawler::live_chapter_count_for_source_manga(&pool, "target", "foo")
+            .await
+            .unwrap(),
+        2
+    );
+    // Soft-drop one source row — count drops by one, the row stays.
+    sqlx::query(
+        "UPDATE chapter_sources SET dropped_at = NOW() WHERE source_chapter_key = '2'",
+    )
+    .execute(&pool)
+    .await
+    .unwrap();
+    assert_eq!(
+        crawler::live_chapter_count_for_source_manga(&pool, "target", "foo")
+            .await
+            .unwrap(),
+        1
+    );
+}
+
 /// Real-world sources publish multiple chapters at the same number
 /// (different uploaders, translator notes, re-releases). After the
 /// (manga_id, number) UNIQUE drop in 0013, each `SourceChapterRef`
@@ -309,59 +371,223 @@ async fn sync_chapters_keeps_duplicate_numbered_chapters_as_separate_rows(pool:
 }
 
 #[sqlx::test(migrations = "./migrations")]
-async fn mark_dropped_mangas_only_drops_unseen(pool: PgPool) {
+async fn sync_chapters_isolates_colliding_keys_across_mangas(pool: PgPool) {
+    // Two mangas, both with a chapter whose source_chapter_key is
+    // "chapter-1". Pre-migration-0017 the PK enforced (source_id,
+    // source_chapter_key) globally and the lookup didn't filter by
+    // manga_id, so the second manga's sync would adopt the first manga's
+    // chapter_id (silent attribution corruption). After 0017 each manga
+    // owns its own row.
     crawler::ensure_source(&pool, "target", "T", "https://x.example")
         .await
         .unwrap();
-    // Seed two mangas before "now" so a later run_started_at sees them as stale.
-    let _ = crawler::upsert_manga_from_source(
-        &pool,
-        "target",
-        "https://x.example/foo",
-        &sample_manga("foo", "Foo", "hf"),
-    )
-    .await
-    .unwrap();
-    let _ = crawler::upsert_manga_from_source(
-        &pool,
-        "target",
-        "https://x.example/bar",
-        &sample_manga("bar", "Bar", "hb"),
-    )
-    .await
-    .unwrap();
-
-    // Now mark a new "run" beginning. Re-upsert only `foo` — `bar`
-    // should be the one flagged dropped.
-    let run_started = chrono::Utc::now();
-    // Sleep briefly so the second upsert's NOW() > run_started_at.
-    tokio::time::sleep(std::time::Duration::from_millis(20)).await;
-    let _ = crawler::upsert_manga_from_source(
-        &pool,
-        "target",
-        "https://x.example/foo",
-        &sample_manga("foo", "Foo", "hf"),
-    )
-    .await
-    .unwrap();
-
-    let n = crawler::mark_dropped_mangas(&pool, "target", run_started)
+    let m1 = sample_manga("foo", "Manga Foo", "hash-foo");
+    let m2 = sample_manga("bar", "Manga Bar", "hash-bar");
+    let up1 = crawler::upsert_manga_from_source(&pool, "target", "https://x.example/foo", &m1)
         .await
         .unwrap();
-    assert_eq!(n, 1, "only bar should have been dropped");
+    let up2 = crawler::upsert_manga_from_source(&pool, "target", "https://x.example/bar", &m2)
+        .await
+        .unwrap();
+    assert_ne!(up1.manga_id, up2.manga_id);
 
-    let foo_dropped: (Option<chrono::DateTime<chrono::Utc>>,) =
-        sqlx::query_as("SELECT dropped_at FROM manga_sources WHERE source_manga_key = 'foo'")
-            .fetch_one(&pool)
-            .await
-            .unwrap();
-    assert!(foo_dropped.0.is_none(), "foo seen this run, must not be dropped");
-    let bar_dropped: (Option<chrono::DateTime<chrono::Utc>>,) =
-        sqlx::query_as("SELECT dropped_at FROM manga_sources WHERE source_manga_key = 'bar'")
-            .fetch_one(&pool)
-            .await
-            .unwrap();
-    assert!(bar_dropped.0.is_some());
+    let shared = vec![SourceChapterRef {
+        source_chapter_key: "chapter-1".into(),
+        number: 1,
+        title: Some("Ch.1".into()),
+        url: "https://x.example/foo/chapter-1/".into(),
+    }];
+    let diff1 = crawler::sync_manga_chapters(&pool, "target", up1.manga_id, &shared)
+        .await
+        .unwrap();
+    assert_eq!(diff1.new, 1, "manga foo: chapter inserted fresh");
+
+    // Manga bar now syncs *the same key*. Under the old schema this would
+    // either fail on PK conflict or attribute the chapter to foo. Under
+    // the new schema bar gets its own chapter row.
+    let bar_chapters = vec![SourceChapterRef {
+        source_chapter_key: "chapter-1".into(),
+        number: 1,
+        title: Some("Ch.1 (bar)".into()),
+        url: "https://x.example/bar/chapter-1/".into(),
+    }];
+    let diff2 = crawler::sync_manga_chapters(&pool, "target", up2.manga_id, &bar_chapters)
+        .await
+        .unwrap();
+    assert_eq!(
+        diff2.new, 1,
+        "manga bar: same key resolved per-manga to a fresh row"
+    );
+
+    let foo_count: (i64,) = sqlx::query_as(
+        "SELECT COUNT(*) FROM chapters WHERE manga_id = $1",
+    )
+    .bind(up1.manga_id)
+    .fetch_one(&pool)
+    .await
+    .unwrap();
+    let bar_count: (i64,) = sqlx::query_as(
+        "SELECT COUNT(*) FROM chapters WHERE manga_id = $1",
+    )
+    .bind(up2.manga_id)
+    .fetch_one(&pool)
+    .await
+    .unwrap();
+    assert_eq!(foo_count.0, 1);
+    assert_eq!(bar_count.0, 1);
+
+    let bar_title: (Option<String>,) = sqlx::query_as(
+        "SELECT title FROM chapters WHERE manga_id = $1 AND number = 1",
+    )
+    .bind(up2.manga_id)
+    .fetch_one(&pool)
+    .await
+    .unwrap();
+    assert_eq!(
+        bar_title.0.as_deref(),
+        Some("Ch.1 (bar)"),
+        "bar's chapter has bar's title, not foo's"
+    );
+
+    // A subsequent re-sync of foo with the same key correctly refreshes
+    // foo's row, not bar's.
+    let foo_resync = vec![SourceChapterRef {
+        source_chapter_key: "chapter-1".into(),
+        number: 1,
+        title: Some("Ch.1 (foo updated)".into()),
+        url: "https://x.example/foo/chapter-1/".into(),
+    }];
+    let diff_refresh = crawler::sync_manga_chapters(&pool, "target", up1.manga_id, &foo_resync)
+        .await
+        .unwrap();
+    assert_eq!(diff_refresh.refreshed, 1);
+    assert_eq!(diff_refresh.new, 0);
+
+    let foo_title: (Option<String>,) = sqlx::query_as(
+        "SELECT title FROM chapters WHERE manga_id = $1 AND number = 1",
+    )
+    .bind(up1.manga_id)
+    .fetch_one(&pool)
+    .await
+    .unwrap();
+    assert_eq!(foo_title.0.as_deref(), Some("Ch.1 (foo updated)"));
+    let bar_title_after: (Option<String>,) = sqlx::query_as(
+        "SELECT title FROM chapters WHERE manga_id = $1 AND number = 1",
+    )
+    .bind(up2.manga_id)
+    .fetch_one(&pool)
+    .await
+    .unwrap();
+    assert_eq!(
+        bar_title_after.0.as_deref(),
+        Some("Ch.1 (bar)"),
+        "bar's row is untouched by foo's refresh"
+    );
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn sync_chapters_serializes_concurrent_calls_for_same_manga(pool: PgPool) {
+    // Without the per-manga advisory lock, two concurrent calls would
+    // both read `seen_keys`, both run the drop UPDATE filtered on `NOT
+    // (key = ANY $3)`, and the later commit could soft-drop a chapter
+    // the earlier had just inserted. The lock makes the calls strictly
+    // sequential per-manga: whichever runs second sees the first one's
+    // committed chapters and treats their absence as a "dropped" signal
+    // only if the second list legitimately omits them.
+    //
+    // Concretely: pre-state [A]. Call X syncs [A, B]; call Y syncs
+    // [A, B, C]. Whatever the schedule, the final state must include
+    // *all three* chapters because neither call legitimately omits the
+    // other's contribution — both lists are supersets of each other's
+    // pre-existing rows.
+    crawler::ensure_source(&pool, "target", "T", "https://x.example")
+        .await
+        .unwrap();
+    let m = sample_manga("foo", "Foo Manga", "hash-1");
+    let up = crawler::upsert_manga_from_source(&pool, "target", "https://x.example/foo", &m)
+        .await
+        .unwrap();
+    let manga_id = up.manga_id;
+
+    // Pre-state: [A].
+    let pre = vec![SourceChapterRef {
+        source_chapter_key: "A".into(),
+        number: 1,
+        title: Some("Ch.A".into()),
+        url: "https://x.example/foo/A".into(),
+    }];
+    crawler::sync_manga_chapters(&pool, "target", manga_id, &pre)
+        .await
+        .unwrap();
+
+    // Two concurrent calls. Call X adds B; call Y adds B + C. Both keep
+    // A. Their drop branches would otherwise race against each other.
+    let list_x = vec![
+        SourceChapterRef {
+            source_chapter_key: "A".into(),
+            number: 1,
+            title: Some("Ch.A".into()),
+            url: "https://x.example/foo/A".into(),
+        },
+        SourceChapterRef {
+            source_chapter_key: "B".into(),
+            number: 2,
+            title: Some("Ch.B".into()),
+            url: "https://x.example/foo/B".into(),
+        },
+    ];
+    let list_y = vec![
+        SourceChapterRef {
+            source_chapter_key: "A".into(),
+            number: 1,
+            title: Some("Ch.A".into()),
+            url: "https://x.example/foo/A".into(),
+        },
+        SourceChapterRef {
+            source_chapter_key: "B".into(),
+            number: 2,
+            title: Some("Ch.B".into()),
+            url: "https://x.example/foo/B".into(),
+        },
+        SourceChapterRef {
+            source_chapter_key: "C".into(),
+            number: 3,
+            title: Some("Ch.C".into()),
+            url: "https://x.example/foo/C".into(),
+        },
+    ];
+    let pool_x = pool.clone();
+    let pool_y = pool.clone();
+    let (rx, ry) = tokio::join!(
+        tokio::spawn(async move {
+            crawler::sync_manga_chapters(&pool_x, "target", manga_id, &list_x).await
+        }),
+        tokio::spawn(async move {
+            crawler::sync_manga_chapters(&pool_y, "target", manga_id, &list_y).await
+        }),
+    );
+    rx.unwrap().expect("call X");
+    ry.unwrap().expect("call Y");
+
+    // All three keys must survive with dropped_at NULL — the lock
+    // ensures the later call sees the earlier one's INSERTs and the
+    // drop UPDATE finds nothing to drop.
+    let alive: Vec<String> = sqlx::query_scalar(
+        "SELECT cs.source_chapter_key \
+           FROM chapter_sources cs \
+           JOIN chapters ch ON ch.id = cs.chapter_id \
+          WHERE ch.manga_id = $1 AND cs.dropped_at IS NULL \
+          ORDER BY cs.source_chapter_key",
+    )
+    .bind(manga_id)
+    .fetch_all(&pool)
+    .await
+    .unwrap();
+    assert_eq!(
+        alive,
+        vec!["A".to_string(), "B".to_string(), "C".to_string()],
+        "all chapters survive concurrent syncs that both contain them"
+    );
 }
 
 #[sqlx::test(migrations = "./migrations")]
@@ -440,6 +666,271 @@ async fn arbitrary_genres_from_source_get_inserted(pool: PgPool) {
     assert_eq!(webtoons_count.0, 1, "case-insensitive lookup reuses the existing row");
 }
 
+/// User-attached tags (rows with non-NULL `added_by` in `manga_tags`)
+/// must survive a crawler upsert. The crawler owns source-attached tags
+/// (added_by IS NULL); user attachments are owned by the user who made
+/// them and the recurring metadata pass must not delete them.
+#[sqlx::test(migrations = "./migrations")]
+async fn sync_tags_preserves_user_attached_tags(pool: PgPool) {
+    crawler::ensure_source(&pool, "target", "T", "https://x.example")
+        .await
+        .unwrap();
+    let m = sample_manga("foo", "Foo Manga", "hash-1");
+    let up = crawler::upsert_manga_from_source(&pool, "target", "https://x.example/foo", &m)
+        .await
+        .unwrap();
+
+    // A real user attaches a personal tag.
+    let user = mangalord::repo::user::create(&pool, "alice", "phc-stub")
+        .await
+        .unwrap();
+    let outcome = mangalord::repo::tag::attach_to_manga(&pool, up.manga_id, "personal", user.id)
+        .await
+        .unwrap();
+    assert!(outcome.created_attachment);
+
+    // Second crawler pass. Use a different metadata_hash so the upsert
+    // takes the Updated branch, but the bug also fires on Unchanged
+    // ticks since sync_tags runs unconditionally.
+    let mut m2 = m.clone();
+    m2.metadata_hash = "hash-2".into();
+    m2.tags = vec!["popular".into(), "weekly".into()];
+    let _ = crawler::upsert_manga_from_source(&pool, "target", "https://x.example/foo", &m2)
+        .await
+        .unwrap();
+
+    // The user tag must still be attached.
+    let user_tag_rows: (i64,) = sqlx::query_as(
+        "SELECT COUNT(*) FROM manga_tags mt \
+           JOIN tags t ON t.id = mt.tag_id \
+          WHERE mt.manga_id = $1 AND lower(t.name) = 'personal' \
+            AND mt.added_by = $2",
+    )
+    .bind(up.manga_id)
+    .bind(user.id)
+    .fetch_one(&pool)
+    .await
+    .unwrap();
+    assert_eq!(
+        user_tag_rows.0, 1,
+        "user-attached tag must survive a crawler upsert"
+    );
+
+    // The source's tags should still attach as well, as crawler-owned.
+    let source_tag_rows: (i64,) = sqlx::query_as(
+        "SELECT COUNT(*) FROM manga_tags mt \
+           JOIN tags t ON t.id = mt.tag_id \
+          WHERE mt.manga_id = $1 \
+            AND mt.added_by IS NULL \
+            AND lower(t.name) IN ('popular', 'weekly')",
+    )
+    .bind(up.manga_id)
+    .fetch_one(&pool)
+    .await
+    .unwrap();
+    assert_eq!(source_tag_rows.0, 2, "source tags re-attach on each pass");
+
+    // A subsequent pass where the source drops a previously-seen tag
+    // must clear that crawler-owned attachment (otherwise crawler-tags
+    // would only ever accumulate).
+    let mut m3 = m2.clone();
+    m3.metadata_hash = "hash-3".into();
+    m3.tags = vec!["popular".into()];
+    let _ = crawler::upsert_manga_from_source(&pool, "target", "https://x.example/foo", &m3)
+        .await
+        .unwrap();
+    let weekly_rows: (i64,) = sqlx::query_as(
+        "SELECT COUNT(*) FROM manga_tags mt \
+           JOIN tags t ON t.id = mt.tag_id \
+          WHERE mt.manga_id = $1 AND lower(t.name) = 'weekly'",
+    )
+    .bind(up.manga_id)
+    .fetch_one(&pool)
+    .await
+    .unwrap();
+    assert_eq!(weekly_rows.0, 0, "source-owned tag dropped by source goes away");
+
+    // And the user tag still survives that third pass.
+    let user_tag_rows: (i64,) = sqlx::query_as(
+        "SELECT COUNT(*) FROM manga_tags mt \
+           JOIN tags t ON t.id = mt.tag_id \
+          WHERE mt.manga_id = $1 AND lower(t.name) = 'personal' \
+            AND mt.added_by = $2",
+    )
+    .bind(up.manga_id)
+    .bind(user.id)
+    .fetch_one(&pool)
+    .await
+    .unwrap();
+    assert_eq!(user_tag_rows.0, 1);
+}
+
+/// `manga_tags.added_by` is `ON DELETE SET NULL` on the user FK. When
+/// the attaching user is deleted, their attachments become orphans
+/// indistinguishable from crawler-owned rows — and the crawler should
+/// reap them on the next pass. Pins the semantic so a future change
+/// can't quietly leave orphan rows lying around.
+#[sqlx::test(migrations = "./migrations")]
+async fn sync_tags_garbage_collects_orphan_user_attachments(pool: PgPool) {
+    crawler::ensure_source(&pool, "target", "T", "https://x.example")
+        .await
+        .unwrap();
+    let m = sample_manga("foo", "Foo", "hash-1");
+    let up = crawler::upsert_manga_from_source(&pool, "target", "https://x.example/foo", &m)
+        .await
+        .unwrap();
+
+    // A user attaches "personal", then the user gets deleted. The
+    // attachment row stays (manga_tags.manga_id FK is CASCADE on
+    // mangas only; we never CASCADE-delete user attachments). The FK
+    // on added_by is `ON DELETE SET NULL`, so the row's owner column
+    // goes NULL — same shape as a crawler-owned row.
+    let user = mangalord::repo::user::create(&pool, "bob", "phc-stub")
+        .await
+        .unwrap();
+    let _ = mangalord::repo::tag::attach_to_manga(&pool, up.manga_id, "personal", user.id)
+        .await
+        .unwrap();
+    sqlx::query("DELETE FROM users WHERE id = $1")
+        .bind(user.id)
+        .execute(&pool)
+        .await
+        .unwrap();
+
+    // Sanity: the orphan still exists post-user-delete with added_by NULL.
+    let (orphan_rows,): (i64,) = sqlx::query_as(
+        "SELECT COUNT(*) FROM manga_tags mt \
+           JOIN tags t ON t.id = mt.tag_id \
+          WHERE mt.manga_id = $1 AND lower(t.name) = 'personal' \
+            AND mt.added_by IS NULL",
+    )
+    .bind(up.manga_id)
+    .fetch_one(&pool)
+    .await
+    .unwrap();
+    assert_eq!(orphan_rows, 1);
+
+    // Next crawler pass — orphan should be reaped along with any
+    // other source-owned rows that aren't in the new tag list.
+    let mut m2 = m.clone();
+    m2.metadata_hash = "hash-2".into();
+    m2.tags = vec!["popular".into()];
+    let _ = crawler::upsert_manga_from_source(&pool, "target", "https://x.example/foo", &m2)
+        .await
+        .unwrap();
+    let (orphan_rows,): (i64,) = sqlx::query_as(
+        "SELECT COUNT(*) FROM manga_tags mt \
+           JOIN tags t ON t.id = mt.tag_id \
+          WHERE mt.manga_id = $1 AND lower(t.name) = 'personal'",
+    )
+    .bind(up.manga_id)
+    .fetch_one(&pool)
+    .await
+    .unwrap();
+    assert_eq!(orphan_rows, 0, "orphan user-attached tag should be reaped");
+}
+
+// ---- list_missing_covers ---------------------------------------------------
+
+#[sqlx::test(migrations = "./migrations")]
+async fn list_missing_covers_only_returns_rows_without_cover(pool: PgPool) {
+    crawler::ensure_source(&pool, "target", "T", "https://x.example")
+        .await
+        .unwrap();
+    let with_cover = sample_manga("with", "With Cover", "h1");
+    let without_cover = sample_manga("without", "No Cover", "h2");
+    let _w = crawler::upsert_manga_from_source(&pool, "target", "https://x.example/with", &with_cover)
+        .await
+        .unwrap();
+    let nc = crawler::upsert_manga_from_source(&pool, "target", "https://x.example/without", &without_cover)
+        .await
+        .unwrap();
+
+    // Manually set a cover for `with` only.
+    sqlx::query("UPDATE mangas SET cover_image_path = 'mangas/x/cover.jpg' WHERE id = $1")
+        .bind(_w.manga_id)
+        .execute(&pool)
+        .await
+        .unwrap();
+
+    let entries = crawler::list_missing_covers(&pool, 50).await.unwrap();
+    assert_eq!(entries.len(), 1, "exactly the manga without a cover");
+    assert_eq!(entries[0].manga_id, nc.manga_id);
+    assert_eq!(entries[0].source_manga_key, "without");
+    assert_eq!(entries[0].source_url, "https://x.example/without");
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn list_missing_covers_skips_dropped_source_rows(pool: PgPool) {
+    crawler::ensure_source(&pool, "target", "T", "https://x.example")
+        .await
+        .unwrap();
+    let m = sample_manga("foo", "Foo", "h1");
+    let up = crawler::upsert_manga_from_source(&pool, "target", "https://x.example/foo", &m)
+        .await
+        .unwrap();
+    sqlx::query("UPDATE manga_sources SET dropped_at = NOW() WHERE manga_id = $1")
+        .bind(up.manga_id)
+        .execute(&pool)
+        .await
+        .unwrap();
+
+    let entries = crawler::list_missing_covers(&pool, 50).await.unwrap();
+    assert!(
+        entries.is_empty(),
+        "dropped-source mangas must not be backfilled — no live source to fetch from"
+    );
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn list_missing_covers_respects_limit(pool: PgPool) {
+    crawler::ensure_source(&pool, "target", "T", "https://x.example")
+        .await
+        .unwrap();
+    for i in 0..5 {
+        let key = format!("m{i}");
+        let url = format!("https://x.example/{key}");
+        let m = sample_manga(&key, &format!("M{i}"), &format!("h{i}"));
+        let _ = crawler::upsert_manga_from_source(&pool, "target", &url, &m)
+            .await
+            .unwrap();
+    }
+    let entries = crawler::list_missing_covers(&pool, 3).await.unwrap();
+    assert_eq!(entries.len(), 3, "limit caps the result set");
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn list_missing_covers_deduplicates_per_manga(pool: PgPool) {
+    // A manga surfaced by two sources should produce ONE backfill
+    // entry, not two — otherwise the per-tick cap could be eaten by
+    // duplicates and starve other mangas.
+    crawler::ensure_source(&pool, "src-a", "A", "https://a.example")
+        .await
+        .unwrap();
+    crawler::ensure_source(&pool, "src-b", "B", "https://b.example")
+        .await
+        .unwrap();
+    let m = sample_manga("foo", "Foo", "h1");
+    let up = crawler::upsert_manga_from_source(&pool, "src-a", "https://a.example/foo", &m)
+        .await
+        .unwrap();
+    // Second source attaches to the SAME manga row.
+    sqlx::query(
+        "INSERT INTO manga_sources (source_id, source_manga_key, manga_id, source_url) \
+         VALUES ($1, $2, $3, $4)",
+    )
+    .bind("src-b")
+    .bind("foo-on-b")
+    .bind(up.manga_id)
+    .bind("https://b.example/foo")
+    .execute(&pool)
+    .await
+    .unwrap();
+
+    let entries = crawler::list_missing_covers(&pool, 50).await.unwrap();
+    assert_eq!(entries.len(), 1, "DISTINCT ON (m.id) collapses duplicate source rows");
+}
+
 #[sqlx::test(migrations = "./migrations")]
 async fn re_appearing_manga_clears_dropped_at(pool: PgPool) {
     crawler::ensure_source(&pool, "target", "T", "https://x.example")
@@ -471,3 +962,261 @@ async fn re_appearing_manga_clears_dropped_at(pool: PgPool) {
     assert!(dropped.0.is_none());
     assert_eq!(dropped.1, up.manga_id);
 }
+
+// ---- source_index: site-order preservation ----
+//
+// The user-facing chapter list reverses the source-site order so that
+// the oldest chapter appears first. The crawler records each row's DOM
+// position in `chapters.source_index` (0 = first in source DOM = newest
+// on this site) on every sync; the list query orders by source_index
+// DESC NULLS LAST, falling through to number/created_at for rows with
+// no source row (e.g. user uploads).
+
+#[sqlx::test(migrations = "./migrations")]
+async fn source_index_set_on_insert_matches_dom_order(pool: PgPool) {
+    crawler::ensure_source(&pool, "target", "T", "https://x.example")
+        .await
+        .unwrap();
+    let m = sample_manga("foo", "Foo Manga", "hash-1");
+    let up = crawler::upsert_manga_from_source(&pool, "target", "https://x.example/foo", &m)
+        .await
+        .unwrap();
+
+    let chapters = vec![
+        SourceChapterRef {
+            source_chapter_key: "a".into(),
+            number: 30,
+            title: Some("Ch.30".into()),
+            url: "https://x.example/foo/a".into(),
+        },
+        SourceChapterRef {
+            source_chapter_key: "b".into(),
+            number: 29,
+            title: Some("Ch.29".into()),
+            url: "https://x.example/foo/b".into(),
+        },
+        SourceChapterRef {
+            source_chapter_key: "c".into(),
+            number: 28,
+            title: Some("Ch.28".into()),
+            url: "https://x.example/foo/c".into(),
+        },
+    ];
+    crawler::sync_manga_chapters(&pool, "target", up.manga_id, &chapters)
+        .await
+        .unwrap();
+
+    let rows: Vec<(String, Option<i32>)> = sqlx::query_as(
+        "SELECT cs.source_chapter_key, c.source_index \
+           FROM chapters c \
+           JOIN chapter_sources cs ON cs.chapter_id = c.id \
+          WHERE c.manga_id = $1 \
+          ORDER BY cs.source_chapter_key",
+    )
+    .bind(up.manga_id)
+    .fetch_all(&pool)
+    .await
+    .unwrap();
+    assert_eq!(
+        rows,
+        vec![
+            ("a".to_string(), Some(0)),
+            ("b".to_string(), Some(1)),
+            ("c".to_string(), Some(2)),
+        ],
+        "source_index reflects enumerate() position in the input slice",
+    );
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn source_index_rewritten_on_resync_when_new_chapter_prepended(pool: PgPool) {
+    crawler::ensure_source(&pool, "target", "T", "https://x.example")
+        .await
+        .unwrap();
+    let m = sample_manga("foo", "Foo Manga", "hash-1");
+    let up = crawler::upsert_manga_from_source(&pool, "target", "https://x.example/foo", &m)
+        .await
+        .unwrap();
+
+    let first = vec![
+        SourceChapterRef {
+            source_chapter_key: "a".into(),
+            number: 1,
+            title: Some("Ch.1".into()),
+            url: "https://x.example/foo/a".into(),
+        },
+        SourceChapterRef {
+            source_chapter_key: "b".into(),
+            number: 2,
+            title: Some("Ch.2".into()),
+            url: "https://x.example/foo/b".into(),
+        },
+    ];
+    crawler::sync_manga_chapters(&pool, "target", up.manga_id, &first)
+        .await
+        .unwrap();
+
+    // Second sync: a brand-new chapter appears at the top of the source
+    // (newest first on the site). All existing rows must shift their
+    // source_index down by one so the display order stays correct.
+    let second = vec![
+        SourceChapterRef {
+            source_chapter_key: "new".into(),
+            number: 3,
+            title: Some("Ch.3".into()),
+            url: "https://x.example/foo/new".into(),
+        },
+        SourceChapterRef {
+            source_chapter_key: "a".into(),
+            number: 1,
+            title: Some("Ch.1".into()),
+            url: "https://x.example/foo/a".into(),
+        },
+        SourceChapterRef {
+            source_chapter_key: "b".into(),
+            number: 2,
+            title: Some("Ch.2".into()),
+            url: "https://x.example/foo/b".into(),
+        },
+    ];
+    crawler::sync_manga_chapters(&pool, "target", up.manga_id, &second)
+        .await
+        .unwrap();
+
+    let rows: Vec<(String, Option<i32>)> = sqlx::query_as(
+        "SELECT cs.source_chapter_key, c.source_index \
+           FROM chapters c \
+           JOIN chapter_sources cs ON cs.chapter_id = c.id \
+          WHERE c.manga_id = $1 \
+          ORDER BY cs.source_chapter_key",
+    )
+    .bind(up.manga_id)
+    .fetch_all(&pool)
+    .await
+    .unwrap();
+    assert_eq!(
+        rows,
+        vec![
+            ("a".to_string(), Some(1)),
+            ("b".to_string(), Some(2)),
+            ("new".to_string(), Some(0)),
+        ],
+        "new chapter takes index 0, existing rows shift down on UPDATE",
+    );
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn list_for_manga_returns_source_order_reversed(pool: PgPool) {
+    crawler::ensure_source(&pool, "target", "T", "https://x.example")
+        .await
+        .unwrap();
+    let m = sample_manga("foo", "Foo Manga", "hash-1");
+    let up = crawler::upsert_manga_from_source(&pool, "target", "https://x.example/foo", &m)
+        .await
+        .unwrap();
+
+    // Site DOM order (top-down = newest-first):
+    //   ch11  (number = 11)
+    //   notice (number = 0, non-numeric label on the site)
+    //   ch10  (number = 10)
+    // Numbers deliberately disagree with DOM order: a number-based sort
+    // would put notice first, but the site places it between ch10 and
+    // ch11. Reversed-DOM display should yield [ch10, notice, ch11].
+    let chapters = vec![
+        SourceChapterRef {
+            source_chapter_key: "ch11".into(),
+            number: 11,
+            title: Some("Ch.11 : Official".into()),
+            url: "https://x.example/foo/11".into(),
+        },
+        SourceChapterRef {
+            source_chapter_key: "notice".into(),
+            number: 0,
+            title: Some("notice. : Officials".into()),
+            url: "https://x.example/foo/notice".into(),
+        },
+        SourceChapterRef {
+            source_chapter_key: "ch10".into(),
+            number: 10,
+            title: Some("Ch.10 : Official".into()),
+            url: "https://x.example/foo/10".into(),
+        },
+    ];
+    crawler::sync_manga_chapters(&pool, "target", up.manga_id, &chapters)
+        .await
+        .unwrap();
+
+    let listed = chapter_repo::list_for_manga(&pool, up.manga_id, 50, 0)
+        .await
+        .unwrap();
+    let keys: Vec<String> = listed
+        .iter()
+        .map(|c| c.title.clone().unwrap_or_default())
+        .collect();
+    assert_eq!(
+        keys,
+        vec![
+            "Ch.10 : Official".to_string(),
+            "notice. : Officials".to_string(),
+            "Ch.11 : Official".to_string(),
+        ],
+        "list returns chapters in reversed source-DOM order, so the \
+         oldest appears first and non-numeric entries land where the \
+         site placed them",
+    );
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn list_for_manga_places_null_source_index_last(pool: PgPool) {
+    crawler::ensure_source(&pool, "target", "T", "https://x.example")
+        .await
+        .unwrap();
+    let m = sample_manga("foo", "Foo Manga", "hash-1");
+    let up = crawler::upsert_manga_from_source(&pool, "target", "https://x.example/foo", &m)
+        .await
+        .unwrap();
+
+    // Crawled chapters get source_index 0 and 1; the upload path leaves
+    // it NULL. NULLS LAST plus the (number, created_at) tail means the
+    // upload sits after both crawled rows even though its number is in
+    // the middle.
+    let crawled = vec![
+        SourceChapterRef {
+            source_chapter_key: "a".into(),
+            number: 1,
+            title: Some("Ch.1".into()),
+            url: "https://x.example/foo/a".into(),
+        },
+        SourceChapterRef {
+            source_chapter_key: "b".into(),
+            number: 3,
+            title: Some("Ch.3".into()),
+            url: "https://x.example/foo/b".into(),
+        },
+    ];
+    crawler::sync_manga_chapters(&pool, "target", up.manga_id, &crawled)
+        .await
+        .unwrap();
+
+    chapter_repo::create(&pool, up.manga_id, 2, Some("User upload Ch.2"), None)
+        .await
+        .unwrap();
+
+    let listed = chapter_repo::list_for_manga(&pool, up.manga_id, 50, 0)
+        .await
+        .unwrap();
+    let titles: Vec<String> = listed
+        .iter()
+        .map(|c| c.title.clone().unwrap_or_default())
+        .collect();
+    assert_eq!(
+        titles,
+        vec![
+            "Ch.3".to_string(),
+            "Ch.1".to_string(),
+            "User upload Ch.2".to_string(),
+        ],
+        "crawled rows ordered by reversed source_index; user upload \
+         (NULL source_index) falls through to the end",
+    );
+}

backend/tests/repo_chapter.rs

@@ -0,0 +1,162 @@
+//! Integration tests for `repo::chapter` — focused on
+//! `dispatch_target`, the resolver the daemon's chapter dispatcher
+//! uses to look up the URL it needs to hand to
+//! `content::sync_chapter_content`.
+//!
+//! The query must:
+//! 1. Skip `chapter_sources` rows where `dropped_at IS NOT NULL` —
+//!    otherwise a soft-dropped source URL is dispatched as if live and
+//!    burns the chapter's retry budget against guaranteed transients.
+//! 2. Order the remaining rows by `last_seen_at DESC` so the freshest
+//!    surviving source is the one we'll fetch from.
+//!
+//! The fix lives in `backend/src/repo/chapter.rs:dispatch_target`. The
+//! enqueue queries at `pipeline.rs:381` and `:435` already filter on
+//! `cs.dropped_at IS NULL`; this brings the resolver into line.
+
+use mangalord::crawler::source::{SourceChapterRef, SourceManga};
+use mangalord::repo::{
+    chapter::dispatch_target,
+    crawler::{ensure_source, sync_manga_chapters, upsert_manga_from_source},
+};
+use sqlx::PgPool;
+use uuid::Uuid;
+
+fn sample_manga(key: &str, title: &str, hash: &str) -> SourceManga {
+    SourceManga {
+        source_manga_key: key.to_string(),
+        title: title.to_string(),
+        alternative_titles: vec![],
+        authors: vec![],
+        genres: vec![],
+        tags: vec![],
+        status: None,
+        summary: None,
+        cover_url: None,
+        chapters: vec![],
+        metadata_hash: hash.to_string(),
+    }
+}
+
+/// Seed a manga with one chapter, plus a second `chapter_sources` row
+/// pointing at the same chapter with a *newer* `last_seen_at` so the
+/// `ORDER BY cs.last_seen_at DESC` branch of the fixed query can
+/// distinguish "freshest live source" from "any live source."
+async fn seed_chapter_with_two_live_sources(pool: &PgPool) -> (Uuid, String, String) {
+    // Two distinct sources both pointing at the same chapter is the
+    // realistic shape of the multi-source state — each source row is
+    // keyed (source_id, chapter_id) after migration 0017.
+    ensure_source(pool, "target", "T", "https://x.example")
+        .await
+        .unwrap();
+    ensure_source(pool, "mirror", "Mirror", "https://m.example")
+        .await
+        .unwrap();
+    let m = sample_manga("foo", "Foo Manga", "hash-1");
+    let up = upsert_manga_from_source(pool, "target", "https://x.example/foo", &m)
+        .await
+        .unwrap();
+    let initial = vec![SourceChapterRef {
+        source_chapter_key: "1".into(),
+        number: 1,
+        title: Some("Ch.1".into()),
+        url: "https://x.example/foo/1/old".into(),
+    }];
+    sync_manga_chapters(pool, "target", up.manga_id, &initial)
+        .await
+        .unwrap();
+
+    let (chapter_id,): (Uuid,) = sqlx::query_as(
+        "SELECT c.id FROM chapters c \
+           JOIN chapter_sources cs ON cs.chapter_id = c.id \
+          WHERE cs.source_chapter_key = '1' AND cs.source_id = 'target'",
+    )
+    .fetch_one(pool)
+    .await
+    .unwrap();
+
+    let old_url = "https://x.example/foo/1/old".to_string();
+    let new_url = "https://m.example/foo/1/mirror".to_string();
+    // Backdate the existing (old/target) source row and add a fresher
+    // row from the mirror source. The fix uses `last_seen_at DESC` to
+    // break the tie deterministically.
+    sqlx::query(
+        "UPDATE chapter_sources \
+            SET last_seen_at = NOW() - INTERVAL '2 days' \
+          WHERE chapter_id = $1 AND source_id = 'target'",
+    )
+    .bind(chapter_id)
+    .execute(pool)
+    .await
+    .unwrap();
+    sqlx::query(
+        "INSERT INTO chapter_sources \
+            (source_id, chapter_id, source_chapter_key, source_url, last_seen_at) \
+         VALUES ('mirror', $1, '1', $2, NOW())",
+    )
+    .bind(chapter_id)
+    .bind(&new_url)
+    .execute(pool)
+    .await
+    .unwrap();
+
+    (chapter_id, old_url, new_url)
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn dispatch_target_prefers_most_recent_live_source(pool: PgPool) {
+    let (chapter_id, _old_url, new_url) =
+        seed_chapter_with_two_live_sources(&pool).await;
+
+    let row = dispatch_target(&pool, chapter_id).await.unwrap();
+    let (_manga_id, source_url) =
+        row.expect("two live sources should yield a dispatch target");
+    assert_eq!(
+        source_url, new_url,
+        "ORDER BY last_seen_at DESC LIMIT 1 must return the freshest source"
+    );
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn dispatch_target_skips_dropped_sources(pool: PgPool) {
+    let (chapter_id, _old_url, new_url) =
+        seed_chapter_with_two_live_sources(&pool).await;
+
+    // Soft-drop the fresher row. The dispatcher must now return the
+    // *older* still-live row instead of the dropped one.
+    sqlx::query(
+        "UPDATE chapter_sources SET dropped_at = NOW() WHERE source_url = $1",
+    )
+    .bind(&new_url)
+    .execute(&pool)
+    .await
+    .unwrap();
+
+    let row = dispatch_target(&pool, chapter_id).await.unwrap();
+    let (_manga_id, source_url) =
+        row.expect("a single live source should still yield a dispatch target");
+    assert!(
+        source_url != new_url,
+        "dispatch_target must not return a dropped source"
+    );
+}
+
+#[sqlx::test(migrations = "./migrations")]
+async fn dispatch_target_returns_none_when_only_dropped_sources_remain(
+    pool: PgPool,
+) {
+    let (chapter_id, _old_url, _new_url) =
+        seed_chapter_with_two_live_sources(&pool).await;
+
+    sqlx::query("UPDATE chapter_sources SET dropped_at = NOW() WHERE chapter_id = $1")
+        .bind(chapter_id)
+        .execute(&pool)
+        .await
+        .unwrap();
+
+    let row = dispatch_target(&pool, chapter_id).await.unwrap();
+    assert!(
+        row.is_none(),
+        "every source is dropped — dispatch_target must return None"
+    );
+}

docker-compose.dev.yml

@@ -17,5 +17,28 @@ services:
       timeout: 5s
       retries: 10
 
+  # Optional: TOR daemon for crawler dev. Ports bind to 127.0.0.1 only
+  # — never the LAN — so a native `cargo run` on the host can reach
+  # 127.0.0.1:9050 / 9051. Mirrors the prod tor service (see
+  # docker-compose.yml), just with host-loopback ports and a default
+  # password baked in for friction-free dev.
+  tor:
+    image: dockurr/tor:latest
+    entrypoint: ["/bin/sh", "/usr/local/bin/mangalord-entrypoint.sh"]
+    environment:
+      PASSWORD: ${TOR_CONTROL_PASSWORD:-dev-tor-password}
+    volumes:
+      - ./tor/torrc:/etc/tor/torrc:ro
+      - ./tor/entrypoint.sh:/usr/local/bin/mangalord-entrypoint.sh:ro
+    ports:
+      - "127.0.0.1:9050:9050"
+      - "127.0.0.1:9051:9051"
+    healthcheck:
+      test: ["CMD-SHELL", "nc -z 127.0.0.1 9050 && nc -z 127.0.0.1 9051"]
+      interval: 5s
+      timeout: 5s
+      retries: 20
+      start_period: 30s
+
 volumes:
   mangalord-postgres-dev:

docker-compose.yml

@@ -1,9 +1,15 @@
+# Production-like compose. Requires a populated `.env` next to this
+# file: at minimum POSTGRES_PASSWORD must be set to a non-default
+# value (the `?required` form below fails fast otherwise). The
+# frontend container expects HTTPS in front (Caddy/Traefik/nginx)
+# because COOKIE_SECURE=true browsers will refuse to send the session
+# cookie over plain HTTP.
 services:
   postgres:
     image: postgres:16-alpine
     environment:
       POSTGRES_USER: ${POSTGRES_USER:-mangalord}
-      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:-mangalord}
+      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:?POSTGRES_PASSWORD must be set in .env}
       POSTGRES_DB: ${POSTGRES_DB:-mangalord}
     volumes:
       - postgres-data:/var/lib/postgresql/data
@@ -13,13 +19,50 @@ services:
       timeout: 5s
       retries: 10
 
+  tor:
+    # SOCKS5 proxy for the crawler, plus a control port so the backend
+    # can signal NEWNYM on bad pages. See tor/torrc for the daemon
+    # config; both ports are only `expose`d (compose-internal), never
+    # bound on the host.
+    #
+    # We bypass dockurr/tor's stock entrypoint because it binds the
+    # control port to localhost (unreachable from the backend
+    # container) and skips its own HashedControlPassword injection
+    # when the user's torrc declares a ControlPort. Our wrapper
+    # (tor/entrypoint.sh) generates the hash from $PASSWORD and execs
+    # tor with our torrc. Backend authenticates with the same plain
+    # string via CRAWLER_TOR_CONTROL_PASSWORD.
+    image: dockurr/tor:latest
+    entrypoint: ["/bin/sh", "/usr/local/bin/mangalord-entrypoint.sh"]
+    environment:
+      PASSWORD: ${TOR_CONTROL_PASSWORD:?TOR_CONTROL_PASSWORD must be set in .env}
+    volumes:
+      - ./tor/torrc:/etc/tor/torrc:ro
+      - ./tor/entrypoint.sh:/usr/local/bin/mangalord-entrypoint.sh:ro
+    expose:
+      - "9050"
+      - "9051"
+    # Wait for both control + SOCKS ports to listen before downstream
+    # services start. dockurr/tor's main process spawns before tor
+    # itself is bound, so `service_started` alone races the first
+    # NEWNYM call.
+    healthcheck:
+      test: ["CMD-SHELL", "nc -z 127.0.0.1 9050 && nc -z 127.0.0.1 9051"]
+      interval: 5s
+      timeout: 5s
+      retries: 20
+      start_period: 30s
+    restart: unless-stopped
+
   backend:
     build: ./backend
     depends_on:
       postgres:
         condition: service_healthy
+      tor:
+        condition: service_healthy
     environment:
-      DATABASE_URL: postgres://${POSTGRES_USER:-mangalord}:${POSTGRES_PASSWORD:-mangalord}@postgres:5432/${POSTGRES_DB:-mangalord}
+      DATABASE_URL: postgres://${POSTGRES_USER:-mangalord}:${POSTGRES_PASSWORD:?POSTGRES_PASSWORD must be set in .env}@postgres:5432/${POSTGRES_DB:-mangalord}
       BIND_ADDRESS: 0.0.0.0:8080
       STORAGE_DIR: /var/lib/mangalord/storage
       RUST_LOG: ${RUST_LOG:-info,mangalord=debug}
@@ -33,6 +76,21 @@ services:
       # Upload limits.
       MAX_REQUEST_BYTES: ${MAX_REQUEST_BYTES:-209715200}
       MAX_FILE_BYTES: ${MAX_FILE_BYTES:-20971520}
+      # System-chromium override for the crawler. Leave blank to use the
+      # bundled fetcher; set to e.g. /usr/bin/chromium-headless-shell on
+      # arm64 deployments. Pair with `--build-arg INSTALL_CHROMIUM=true`
+      # so the image actually contains the binary.
+      CRAWLER_CHROMIUM_BINARY: ${CRAWLER_CHROMIUM_BINARY:-}
+      # TOR proxy + NEWNYM recircuit (see .env.example for details).
+      # Defaults assume the bundled `tor` service above; override
+      # CRAWLER_PROXY=  and CRAWLER_TOR_CONTROL_URL=  (both empty) in
+      # .env to disable. CRAWLER_TOR_CONTROL_PASSWORD MUST match the
+      # tor service's PASSWORD (both wired to the same TOR_CONTROL_PASSWORD
+      # .env var below).
+      CRAWLER_PROXY: ${CRAWLER_PROXY-socks5h://tor:9050}
+      CRAWLER_TOR_CONTROL_URL: ${CRAWLER_TOR_CONTROL_URL-tcp://tor:9051}
+      CRAWLER_TOR_CONTROL_PASSWORD: ${TOR_CONTROL_PASSWORD:?TOR_CONTROL_PASSWORD must be set in .env}
+      CRAWLER_TOR_RECIRCUIT_MAX_ATTEMPTS: ${CRAWLER_TOR_RECIRCUIT_MAX_ATTEMPTS:-3}
     volumes:
       - storage-data:/var/lib/mangalord/storage
     # No host port mapping in the default setup — the frontend proxies

frontend/Dockerfile

@@ -1,7 +1,11 @@
 FROM node:22-alpine AS builder
 WORKDIR /app
 COPY package.json package-lock.json* ./
-RUN npm install
+# `npm ci` installs the locked versions exactly; `npm install` would
+# silently rewrite package-lock.json mid-build. CI (.gitea/workflows)
+# also uses `npm ci`, so this keeps the image build deterministic and
+# matches what the test job validated.
+RUN npm ci
 COPY . .
 RUN npm run build
 
@@ -10,8 +14,22 @@ WORKDIR /app
 ENV NODE_ENV=production
 ENV HOST=0.0.0.0
 ENV PORT=3000
-COPY --from=builder /app/build ./build
-COPY --from=builder /app/node_modules ./node_modules
-COPY --from=builder /app/package.json ./
+
+# node:22-alpine ships a `node` user (UID 1000); use it instead of
+# running the SvelteKit server as root.
+COPY --from=builder --chown=node:node /app/build ./build
+COPY --from=builder --chown=node:node /app/node_modules ./node_modules
+COPY --from=builder --chown=node:node /app/package.json ./
+
+USER node
 EXPOSE 3000
+
+# Alpine's busybox `wget` is the canonical lightweight HTTP probe. Probe
+# 127.0.0.1, not `localhost`: musl resolves `localhost` to IPv6 ::1 first,
+# but the Node server binds IPv4 0.0.0.0 only, so a localhost probe gets
+# "connection refused" and the container is wrongly marked unhealthy. Use a
+# GET (`-O /dev/null`) since `node build` serves 200 on `/`.
+HEALTHCHECK --interval=30s --timeout=5s --start-period=10s --retries=3 \
+  CMD wget -q -O /dev/null http://127.0.0.1:3000/ || exit 1
+
 CMD ["node", "build"]

frontend/e2e/manga-list.spec.ts

@@ -10,6 +10,15 @@ import { test, expect, type Page } from '@playwright/test';
 const emptyPage = { items: [], page: { limit: 50, offset: 0, total: null } };
 
 async function mockAnonymous(page: Page) {
+    // Force public mode so the root +layout.ts doesn't bounce us to /login
+    // (a dev backend with PRIVATE_MODE=true must not leak into E2E runs).
+    await page.route('**/api/v1/auth/config', async (route) => {
+        await route.fulfill({
+            status: 200,
+            contentType: 'application/json',
+            body: JSON.stringify({ self_register_enabled: true, private_mode: false })
+        });
+    });
     await page.route('**/api/v1/auth/me', async (route) => {
         await route.fulfill({
             status: 401,
@@ -69,3 +78,53 @@ test('search updates the manga list', async ({ page }) => {
     await expect(page.getByTestId('manga-list')).toContainText('Berserk');
     expect(lastSearch).toBe('berserk');
 });
+
+test('clicking Next paginates to page 2 and updates the URL', async ({ page }) => {
+    await mockAnonymous(page);
+
+    // Fake a catalogue of 75 mangas; page 1 is ids 1..50, page 2 is ids 51..75.
+    const TOTAL = 75;
+    function mangaAt(i: number) {
+        return {
+            id: `m${i}`,
+            title: `Manga ${i}`,
+            author: 'Test',
+            description: null,
+            cover_image_path: null,
+            created_at: '2026-01-01T00:00:00Z',
+            updated_at: '2026-01-01T00:00:00Z',
+            authors: [],
+            genres: []
+        };
+    }
+
+    await page.route('**/api/v1/mangas*', async (route) => {
+        const url = new URL(route.request().url());
+        const limit = Number(url.searchParams.get('limit') ?? '50');
+        const offset = Number(url.searchParams.get('offset') ?? '0');
+        const items: ReturnType<typeof mangaAt>[] = [];
+        for (let i = offset + 1; i <= Math.min(offset + limit, TOTAL); i++) {
+            items.push(mangaAt(i));
+        }
+        await route.fulfill({
+            status: 200,
+            contentType: 'application/json',
+            body: JSON.stringify({
+                items,
+                page: { limit, offset, total: TOTAL }
+            })
+        });
+    });
+
+    await page.goto('/');
+    await expect(page.getByTestId('manga-total')).toContainText('Showing 1–50 of 75');
+    await expect(page.getByTestId('manga-list')).toContainText('Manga 1');
+    await expect(page.getByTestId('manga-list')).not.toContainText('Manga 75');
+
+    await page.getByTestId('manga-pager').getByRole('button', { name: /next/i }).click();
+
+    await expect(page).toHaveURL(/[?&]page=2(&|$)/);
+    await expect(page.getByTestId('manga-total')).toContainText('Showing 51–75 of 75');
+    await expect(page.getByTestId('manga-list')).toContainText('Manga 75');
+    await expect(page.getByTestId('manga-list')).not.toContainText('Manga 1');
+});

frontend/e2e/page-title.spec.ts

@@ -0,0 +1,67 @@
+import { test, expect, type Page } from '@playwright/test';
+
+// Guards the title-on-nav behavior: without this, a stale title from
+// the last manga / author page lingers when the user navigates to a
+// generic page like /upload.
+
+async function mockAnonymous(page: Page) {
+    await page.route('**/api/v1/auth/config', async (route) => {
+        await route.fulfill({
+            status: 200,
+            contentType: 'application/json',
+            body: JSON.stringify({ self_register_enabled: true, private_mode: false })
+        });
+    });
+    await page.route('**/api/v1/auth/me', async (route) => {
+        await route.fulfill({
+            status: 401,
+            contentType: 'application/json',
+            body: JSON.stringify({ error: { code: 'unauthenticated', message: 'unauthenticated' } })
+        });
+    });
+    await page.route('**/api/v1/mangas*', async (route) => {
+        await route.fulfill({
+            status: 200,
+            contentType: 'application/json',
+            body: JSON.stringify({ items: [], page: { limit: 50, offset: 0, total: 0 } })
+        });
+    });
+}
+
+test('static route titles use the brand-first layout map', async ({ page }) => {
+    await mockAnonymous(page);
+
+    await page.goto('/');
+    await expect(page).toHaveTitle('Mangalord');
+
+    await page.goto('/upload');
+    await expect(page).toHaveTitle('Mangalord | Upload');
+
+    await page.goto('/login');
+    await expect(page).toHaveTitle('Mangalord | Login');
+
+    await page.goto('/bookmarks');
+    await expect(page).toHaveTitle('Mangalord | Bookmarks');
+
+    await page.goto('/collections');
+    await expect(page).toHaveTitle('Mangalord | Collections');
+});
+
+test('title updates when navigating away from a content page', async ({ page }) => {
+    await mockAnonymous(page);
+
+    // Pretend we just left a manga detail page — the document title
+    // would have been overridden to "Mangalord | Berserk". Use evaluate
+    // to set it synthetically so we can assert the regression cleanly
+    // even though the dynamic page itself isn't mocked here.
+    await page.goto('/');
+    await page.evaluate(() => {
+        document.title = 'Mangalord | Berserk';
+    });
+    expect(await page.title()).toBe('Mangalord | Berserk');
+
+    // Client-side nav to /upload — the root layout must reassert its
+    // mapped title or the stale "Berserk" lingers.
+    await page.goto('/upload');
+    await expect(page).toHaveTitle('Mangalord | Upload');
+});

frontend/e2e/private-mode.spec.ts

@@ -0,0 +1,101 @@
+import { test, expect, type Page } from '@playwright/test';
+
+// Network-level mocks for the private-mode UX. The backend integration
+// tests (api_private_mode.rs) cover the actual gate; here we only
+// verify that the SvelteKit universal load redirects anonymous
+// visitors to /login and then back to where they were going.
+
+const userFixture = {
+    id: 'user-1',
+    username: 'alice',
+    created_at: '2026-01-01T00:00:00Z',
+    is_admin: false
+};
+const emptyPage = { items: [], page: { limit: 50, offset: 0, total: null } };
+
+async function stubPrivateInstance(page: Page) {
+    let loggedIn = false;
+
+    // The flag that flips the gate on. Frontend reads it in
+    // `+layout.ts` to decide whether to redirect.
+    await page.route('**/api/v1/auth/config', async (route) => {
+        await route.fulfill({
+            status: 200,
+            contentType: 'application/json',
+            body: JSON.stringify({
+                self_register_enabled: false,
+                private_mode: true
+            })
+        });
+    });
+
+    await page.route('**/api/v1/auth/me', async (route) => {
+        if (loggedIn) {
+            await route.fulfill({
+                status: 200,
+                contentType: 'application/json',
+                body: JSON.stringify({ user: userFixture })
+            });
+        } else {
+            await route.fulfill({
+                status: 401,
+                contentType: 'application/json',
+                body: JSON.stringify({
+                    error: { code: 'unauthenticated', message: 'unauthenticated' }
+                })
+            });
+        }
+    });
+
+    await page.route('**/api/v1/auth/login', async (route) => {
+        loggedIn = true;
+        await route.fulfill({
+            status: 200,
+            contentType: 'application/json',
+            body: JSON.stringify({ user: userFixture })
+        });
+    });
+
+    // The real backend would 401 these too in private mode; we stub
+    // success so the post-login navigation can render the home page
+    // without an additional redirect cycle.
+    await page.route('**/api/v1/mangas*', async (route) => {
+        await route.fulfill({
+            status: 200,
+            contentType: 'application/json',
+            body: JSON.stringify(emptyPage)
+        });
+    });
+}
+
+test('private mode: anonymous visit to / redirects to /login?next=%2F', async ({ page }) => {
+    await stubPrivateInstance(page);
+    await page.goto('/');
+    await expect(page).toHaveURL(/\/login\?next=%2F$/);
+    await expect(page.getByTestId('login-username')).toBeVisible();
+});
+
+test('private mode: register link is hidden', async ({ page }) => {
+    await stubPrivateInstance(page);
+    await page.goto('/login');
+    await expect(page.getByTestId('nav-login')).toBeVisible();
+    // self_register_enabled is the effective value (false in private
+    // mode regardless of ALLOW_SELF_REGISTER), so the navbar must
+    // never render the register affordance here.
+    await expect(page.getByTestId('nav-register')).toHaveCount(0);
+});
+
+test('private mode: after login the user lands back on the requested page', async ({ page }) => {
+    await stubPrivateInstance(page);
+
+    // Visit a deep link → bounced to /login with next= preserving it.
+    await page.goto('/');
+    await expect(page).toHaveURL(/\/login\?next=%2F$/);
+
+    await page.getByTestId('login-username').fill('alice');
+    await page.getByTestId('login-password').fill('hunter2hunter2');
+    await page.getByTestId('login-submit').click();
+
+    // Authenticated → can now reach the home page without bouncing.
+    await expect(page.getByTestId('session-user')).toContainText('alice');
+});

frontend/e2e/reader-chapter-select.spec.ts

@@ -0,0 +1,167 @@
+import { test, expect, type Page } from '@playwright/test';
+
+const mangaId = '33333333-3333-3333-3333-333333333333';
+const chapter1Id = 'c1111111-3333-3333-3333-333333333333';
+const chapter2Id = 'c2222222-3333-3333-3333-333333333333';
+const chapter3Id = 'c3333333-3333-3333-3333-333333333333';
+
+const mangaFixture = {
+    id: mangaId,
+    title: 'Vinland Saga',
+    author: 'Makoto Yukimura',
+    description: null,
+    cover_image_path: null,
+    created_at: '2026-01-01T00:00:00Z',
+    updated_at: '2026-01-01T00:00:00Z'
+};
+
+const chaptersFixture = [
+    {
+        id: chapter1Id,
+        manga_id: mangaId,
+        number: 1,
+        title: 'Somewhere, Not Here',
+        page_count: 1,
+        created_at: '2026-01-01T00:00:00Z'
+    },
+    {
+        id: chapter2Id,
+        manga_id: mangaId,
+        number: 2,
+        title: null,
+        page_count: 1,
+        created_at: '2026-01-02T00:00:00Z'
+    },
+    {
+        id: chapter3Id,
+        manga_id: mangaId,
+        number: 3,
+        title: 'Sword Dance',
+        page_count: 1,
+        created_at: '2026-01-03T00:00:00Z'
+    }
+];
+
+function pageFixture(chapterId: string) {
+    return [
+        {
+            id: `p1111111-${chapterId.slice(1, 8)}-3333-3333-333333333333`,
+            chapter_id: chapterId,
+            page_number: 1,
+            storage_key: `mangas/${mangaId}/chapters/${chapterId}/pages/0001.png`,
+            content_type: 'image/png'
+        }
+    ];
+}
+
+async function mockReaderApis(page: Page) {
+    // Force public mode so the layout doesn't bounce anonymous visitors
+    // to /login (the dev backend on this machine runs with
+    // PRIVATE_MODE=true, which the layout's universal load respects).
+    await page.route('**/api/v1/auth/config', (route) =>
+        route.fulfill({
+            status: 200,
+            contentType: 'application/json',
+            body: JSON.stringify({ self_register_enabled: true, private_mode: false })
+        })
+    );
+    await page.route('**/api/v1/auth/me', (route) =>
+        route.fulfill({
+            status: 401,
+            contentType: 'application/json',
+            body: JSON.stringify({ error: { code: 'unauthenticated', message: '' } })
+        })
+    );
+    await page.route('**/api/v1/auth/me/preferences', (route) =>
+        route.fulfill({
+            status: 401,
+            contentType: 'application/json',
+            body: JSON.stringify({ error: { code: 'unauthenticated', message: '' } })
+        })
+    );
+    await page.route('**/api/v1/me/bookmarks*', (route) =>
+        route.fulfill({
+            status: 401,
+            contentType: 'application/json',
+            body: JSON.stringify({ error: { code: 'unauthenticated', message: '' } })
+        })
+    );
+    await page.route(`**/api/v1/mangas/${mangaId}`, (route) =>
+        route.fulfill({
+            status: 200,
+            contentType: 'application/json',
+            body: JSON.stringify(mangaFixture)
+        })
+    );
+    await page.route(new RegExp(`/api/v1/mangas/${mangaId}/chapters(\\?.*)?$`), (route) =>
+        route.fulfill({
+            status: 200,
+            contentType: 'application/json',
+            body: JSON.stringify({
+                items: chaptersFixture,
+                page: { limit: 200, offset: 0, total: chaptersFixture.length }
+            })
+        })
+    );
+    for (const c of chaptersFixture) {
+        await page.route(`**/api/v1/mangas/${mangaId}/chapters/${c.id}`, (route) =>
+            route.fulfill({
+                status: 200,
+                contentType: 'application/json',
+                body: JSON.stringify(c)
+            })
+        );
+        await page.route(
+            `**/api/v1/mangas/${mangaId}/chapters/${c.id}/pages`,
+            (route) =>
+                route.fulfill({
+                    status: 200,
+                    contentType: 'application/json',
+                    body: JSON.stringify({ pages: pageFixture(c.id) })
+                })
+        );
+    }
+    const png = Buffer.from(
+        '89504e470d0a1a0a0000000d49484452000000010000000108060000001f15c4890000000d49444154789c63000100000005000158a3b62a0000000049454e44ae426082',
+        'hex'
+    );
+    await page.route('**/api/v1/files/**', (route) =>
+        route.fulfill({ status: 200, contentType: 'image/png', body: png })
+    );
+}
+
+test('reader chapter select lists every chapter with the manga-detail-style label', async ({
+    page
+}) => {
+    await mockReaderApis(page);
+    await page.goto(`/manga/${mangaId}/chapter/${chapter2Id}`);
+
+    const select = page.getByTestId('reader-chapter-select');
+    await expect(select).toBeVisible();
+
+    // The current chapter is preselected.
+    await expect(select).toHaveValue(chapter2Id);
+
+    // Each chapter rendered as "Ch. N — Title" (or "Ch. N" when title is null),
+    // in ascending number order — matching the prev/next sort.
+    const labels = await select.locator('option').allTextContents();
+    expect(labels.map((l) => l.trim())).toEqual([
+        'Ch. 1 — Somewhere, Not Here',
+        'Ch. 2',
+        'Ch. 3 — Sword Dance'
+    ]);
+});
+
+test('choosing a chapter from the select navigates to that chapter', async ({ page }) => {
+    await mockReaderApis(page);
+    await page.goto(`/manga/${mangaId}/chapter/${chapter1Id}`);
+
+    await expect(page.getByTestId('reader-chapter-select')).toHaveValue(chapter1Id);
+
+    await page.getByTestId('reader-chapter-select').selectOption(chapter3Id);
+
+    await expect(page).toHaveURL(
+        new RegExp(`/manga/${mangaId}/chapter/${chapter3Id}$`)
+    );
+    await expect(page.getByTestId('reader-chapter-select')).toHaveValue(chapter3Id);
+});

frontend/e2e/reader.spec.ts

@@ -120,7 +120,7 @@ test('manga overview shows title, cover, and a chapter list', async ({ page }) =
     await expect(page.getByTestId('manga-title')).toHaveText('Berserk');
     await expect(page.getByTestId('manga-author')).toContainText('Kentaro Miura');
     await expect(page.getByTestId('manga-cover')).toBeVisible();
-    await expect(page.getByTestId('chapter-list')).toContainText('Chapter 1');
+    await expect(page.getByTestId('chapter-list')).toContainText('The Brand');
     await expect(page.getByTestId('bookmark-signin')).toBeVisible();
 });
 

frontend/package.json

@@ -1,6 +1,6 @@
 {
   "name": "mangalord-frontend",
-  "version": "0.34.0",
+  "version": "0.52.0",
   "private": true,
   "type": "module",
   "scripts": {

frontend/src/hooks.server.test.ts

@@ -118,4 +118,77 @@ describe('hooks.server proxy', () => {
         expect(body.error.code).toBe('upstream_unavailable');
         expect(errSpy).toHaveBeenCalled();
     });
+
+    it('strips every hop-by-hop header listed in RFC 7230 §6.1', async () => {
+        // Defence in depth: axum doesn't emit these, but a future
+        // middleware that did would otherwise leak per-connection
+        // state across the proxy boundary.
+        fetchSpy.mockResolvedValueOnce(new Response('[]', { status: 200 }));
+        const resolve = vi.fn();
+        await handle({
+            event: makeEvent('/api/v1/health', {
+                headers: {
+                    host: 'app.example.com',
+                    'content-length': '0',
+                    connection: 'keep-alive',
+                    'keep-alive': 'timeout=5',
+                    'proxy-authenticate': 'Basic realm=x',
+                    'proxy-authorization': 'Basic xyz',
+                    te: 'trailers',
+                    trailer: 'Expires',
+                    'transfer-encoding': 'chunked',
+                    upgrade: 'websocket',
+                    // A non-hop-by-hop header to ensure non-targets
+                    // aren't accidentally stripped.
+                    'x-custom': 'pass-through'
+                }
+            }),
+            resolve
+        });
+        const init = fetchSpy.mock.calls[0][1] as RequestInit;
+        const headers = init.headers as Headers;
+        for (const h of [
+            'host',
+            'content-length',
+            'connection',
+            'keep-alive',
+            'proxy-authenticate',
+            'proxy-authorization',
+            'te',
+            'trailer',
+            'transfer-encoding',
+            'upgrade'
+        ]) {
+            expect(headers.get(h), `${h} should be stripped`).toBeNull();
+        }
+        expect(headers.get('x-custom')).toBe('pass-through');
+    });
+
+    it('aborts and returns 502 when the upstream stalls past the timeout', async () => {
+        const errSpy = vi.spyOn(console, 'error').mockImplementation(() => {});
+        // Simulate an aborted fetch (AbortController.abort() raises a
+        // DOMException with name 'AbortError' on Node's fetch). The
+        // handler should treat it as the same upstream_unavailable
+        // 502 it uses for any other network failure.
+        const abortErr = new DOMException('aborted', 'AbortError');
+        fetchSpy.mockRejectedValueOnce(abortErr);
+
+        const resolve = vi.fn();
+        const resp = await handle({ event: makeEvent('/api/v1/slow'), resolve });
+        expect(resp.status).toBe(502);
+        const body = await resp.json();
+        expect(body.error.code).toBe('upstream_unavailable');
+        expect(errSpy).toHaveBeenCalled();
+    });
+
+    it('attaches an AbortSignal to the upstream fetch so it can time out', async () => {
+        fetchSpy.mockResolvedValueOnce(new Response('[]', { status: 200 }));
+        const resolve = vi.fn();
+        await handle({ event: makeEvent('/api/v1/health'), resolve });
+        const init = fetchSpy.mock.calls[0][1] as RequestInit;
+        expect(init.signal).toBeInstanceOf(AbortSignal);
+        // The signal hasn't fired (handler returned in time), but its
+        // presence is the contract this test is pinning.
+        expect(init.signal?.aborted).toBe(false);
+    });
 });

frontend/src/hooks.server.ts

@@ -12,20 +12,66 @@ import type { Handle } from '@sveltejs/kit';
 
 const BACKEND_URL = process.env.BACKEND_URL ?? 'http://localhost:8080';
 
+/**
+ * Hop-by-hop headers per RFC 7230 §6.1. These are scoped to a single
+ * transport-level connection and must not be forwarded by a proxy.
+ * Plus `host` and `content-length`: `host` would mislead the backend
+ * about its origin, and `content-length` is recomputed by the upstream
+ * fetch from the body stream.
+ */
+const HOP_BY_HOP_HEADERS = [
+    'host',
+    'content-length',
+    'connection',
+    'keep-alive',
+    'proxy-authenticate',
+    'proxy-authorization',
+    'te',
+    'trailer',
+    'transfer-encoding',
+    'upgrade'
+];
+
+/**
+ * Cap each proxied request at 5 minutes. The bound exists to surface
+ * a wedged backend (stuck on a slow DB query, deadlocked, etc.) as a
+ * 502 rather than letting the browser request hang indefinitely.
+ *
+ * The default leans toward the slow-upload end of the spectrum: at a
+ * 1 Mbps upstream, a 200 MiB chapter upload (the default
+ * `MAX_REQUEST_BYTES` cap) needs ~27 minutes; 300 s covers the more
+ * realistic 25 Mbps urban-broadband case (~64 s for the same upload)
+ * with comfortable headroom. Operators serving very slow clients
+ * should raise `BACKEND_PROXY_TIMEOUT_MS`; operators behind a
+ * tighter upstream proxy may want to lower it. A future improvement
+ * is an idle-based timeout (reset per chunk) instead of this
+ * wall-clock budget — that's a fair bit more code, deferred.
+ */
+const PROXY_TIMEOUT_MS = (() => {
+    const raw = process.env.BACKEND_PROXY_TIMEOUT_MS;
+    const n = raw ? Number(raw) : 300_000;
+    return Number.isFinite(n) && n > 0 ? n : 300_000;
+})();
+
 export const handle: Handle = async ({ event, resolve }) => {
     if (event.url.pathname.startsWith('/api/')) {
         const target = `${BACKEND_URL}${event.url.pathname}${event.url.search}`;
 
-        // Strip hop-by-hop headers — `host` would mislead the backend
-        // about the origin, and `content-length` will be recomputed.
         const headers = new Headers(event.request.headers);
-        headers.delete('host');
-        headers.delete('content-length');
+        for (const h of HOP_BY_HOP_HEADERS) headers.delete(h);
+
+        // AbortController times the upstream fetch out so a backend
+        // wedged on a slow DB query doesn't keep the browser request
+        // hanging forever. The `signal` is also wired into the
+        // RequestInit so the body stream is cancelled cleanly.
+        const ctrl = new AbortController();
+        const timeoutHandle = setTimeout(() => ctrl.abort(), PROXY_TIMEOUT_MS);
 
         const init: RequestInit & { duplex?: 'half' } = {
             method: event.request.method,
             headers,
-            redirect: 'manual'
+            redirect: 'manual',
+            signal: ctrl.signal
         };
         if (event.request.method !== 'GET' && event.request.method !== 'HEAD') {
             init.body = event.request.body;
@@ -39,11 +85,13 @@ export const handle: Handle = async ({ event, resolve }) => {
             upstream = await fetch(target, init);
         } catch (e) {
             // Network-layer failure (DNS / connection refused / TLS
-            // handshake) — most commonly "backend container restarting".
-            // SvelteKit's default 500 would be an HTML page that
-            // client.ts can't .json(), which masks the real cause. Emit
-            // the standard envelope with a dedicated code instead.
+            // handshake / abort by timeout) — most commonly "backend
+            // container restarting". SvelteKit's default 500 would be
+            // an HTML page that client.ts can't .json(), which masks
+            // the real cause. Emit the standard envelope with a
+            // dedicated code instead.
             console.error('Proxy to backend failed:', e);
+            clearTimeout(timeoutHandle);
             return new Response(
                 JSON.stringify({
                     error: {
@@ -58,6 +106,7 @@ export const handle: Handle = async ({ event, resolve }) => {
             );
         }
 
+        clearTimeout(timeoutHandle);
         return new Response(upstream.body, {
             status: upstream.status,
             statusText: upstream.statusText,

frontend/src/lib/api/admin.test.ts

@@ -0,0 +1,331 @@
+import {
+    describe,
+    it,
+    expect,
+    vi,
+    beforeEach,
+    afterEach,
+    type MockInstance
+} from 'vitest';
+import {
+    listAdminUsers,
+    deleteAdminUser,
+    setUserAdmin,
+    createAdminUser,
+    listAdminMangas,
+    listAdminChapters,
+    getSystemStats,
+    resyncManga,
+    resyncChapter
+} from './admin';
+
+function ok(body: unknown, status = 200): Response {
+    return new Response(JSON.stringify(body), {
+        status,
+        headers: { 'content-type': 'application/json' }
+    });
+}
+
+function noContent(): Response {
+    return new Response(null, { status: 204 });
+}
+
+function envelope(status: number, code: string, message: string): Response {
+    return new Response(JSON.stringify({ error: { code, message } }), {
+        status,
+        headers: { 'content-type': 'application/json' }
+    });
+}
+
+const userFixture = {
+    id: 'u-1',
+    username: 'alice',
+    created_at: '2026-01-01T00:00:00Z',
+    is_admin: false
+};
+
+const mangaFixture = {
+    id: 'm-1',
+    title: 'Test',
+    status: 'ongoing',
+    cover_image_path: null,
+    created_at: '2026-01-01T00:00:00Z',
+    updated_at: '2026-01-01T00:00:00Z',
+    sync_state: 'synced' as const,
+    chapter_count: 3,
+    latest_seen_at: '2026-01-02T00:00:00Z'
+};
+
+const systemFixture = {
+    disk: {
+        total_bytes: 1_000_000,
+        used_bytes: 500_000,
+        free_bytes: 500_000,
+        percent_used: 50.0
+    },
+    memory: { total_bytes: 8_000_000, used_bytes: 4_000_000, percent_used: 50.0 },
+    cpu: { percent_used: 12.3 },
+    alerts: []
+};
+
+describe('admin api client', () => {
+    let fetchSpy: MockInstance<typeof globalThis.fetch>;
+
+    beforeEach(() => {
+        fetchSpy = vi.spyOn(globalThis, 'fetch');
+    });
+    afterEach(() => {
+        vi.restoreAllMocks();
+    });
+
+    // ---- users ----
+
+    it('listAdminUsers GETs /v1/admin/users and parses the paged envelope', async () => {
+        fetchSpy.mockResolvedValueOnce(
+            ok({ items: [userFixture], page: { limit: 50, offset: 0, total: 1 } })
+        );
+        const page = await listAdminUsers({ limit: 50 });
+        expect(page.items).toHaveLength(1);
+        expect(page.items[0]).toEqual(userFixture);
+        expect(page.page.total).toBe(1);
+        const url = fetchSpy.mock.calls[0][0] as string;
+        expect(url).toMatch(/\/v1\/admin\/users\?limit=50$/);
+    });
+
+    it('listAdminUsers forwards search + offset query params', async () => {
+        fetchSpy.mockResolvedValueOnce(
+            ok({ items: [], page: { limit: 50, offset: 10, total: 0 } })
+        );
+        await listAdminUsers({ search: 'al', offset: 10 });
+        const url = fetchSpy.mock.calls[0][0] as string;
+        expect(url).toContain('search=al');
+        expect(url).toContain('offset=10');
+    });
+
+    it('listAdminUsers surfaces 403 forbidden via ApiError.code', async () => {
+        fetchSpy.mockResolvedValueOnce(envelope(403, 'forbidden', 'forbidden'));
+        await expect(listAdminUsers()).rejects.toMatchObject({
+            status: 403,
+            code: 'forbidden'
+        });
+    });
+
+    it('deleteAdminUser DELETEs to /v1/admin/users/{id} and handles 204', async () => {
+        fetchSpy.mockResolvedValueOnce(noContent());
+        await expect(deleteAdminUser('u-1')).resolves.toBeUndefined();
+        const url = fetchSpy.mock.calls[0][0] as string;
+        expect(url).toMatch(/\/v1\/admin\/users\/u-1$/);
+        const init = fetchSpy.mock.calls[0][1] as RequestInit;
+        expect(init.method).toBe('DELETE');
+    });
+
+    it('deleteAdminUser surfaces 409 conflict (self-delete / last-admin)', async () => {
+        fetchSpy.mockResolvedValueOnce(
+            envelope(409, 'conflict', 'cannot delete yourself; ask another admin')
+        );
+        await expect(deleteAdminUser('u-1')).rejects.toMatchObject({
+            status: 409,
+            code: 'conflict'
+        });
+    });
+
+    it('createAdminUser POSTs to /v1/admin/users with body and returns the created user', async () => {
+        const created = { ...userFixture, username: 'invited01' };
+        fetchSpy.mockResolvedValueOnce(ok(created, 201));
+        const got = await createAdminUser({
+            username: 'invited01',
+            password: 'freshpass1234'
+        });
+        expect(got).toEqual(created);
+        const url = fetchSpy.mock.calls[0][0] as string;
+        expect(url).toMatch(/\/v1\/admin\/users$/);
+        const init = fetchSpy.mock.calls[0][1] as RequestInit;
+        expect(init.method).toBe('POST');
+        expect(JSON.parse(init.body as string)).toEqual({
+            username: 'invited01',
+            password: 'freshpass1234'
+        });
+    });
+
+    it('createAdminUser forwards is_admin when provided', async () => {
+        const created = { ...userFixture, username: 'coadmin', is_admin: true };
+        fetchSpy.mockResolvedValueOnce(ok(created, 201));
+        await createAdminUser({
+            username: 'coadmin',
+            password: 'freshpass1234',
+            is_admin: true
+        });
+        const init = fetchSpy.mock.calls[0][1] as RequestInit;
+        expect(JSON.parse(init.body as string)).toEqual({
+            username: 'coadmin',
+            password: 'freshpass1234',
+            is_admin: true
+        });
+    });
+
+    it('createAdminUser surfaces 409 conflict on duplicate username', async () => {
+        fetchSpy.mockResolvedValueOnce(
+            envelope(409, 'conflict', 'username is already taken')
+        );
+        await expect(
+            createAdminUser({ username: 'taken', password: 'freshpass1234' })
+        ).rejects.toMatchObject({ status: 409, code: 'conflict' });
+    });
+
+    it('setUserAdmin PATCHes is_admin and returns the updated user', async () => {
+        const updated = { ...userFixture, is_admin: true };
+        fetchSpy.mockResolvedValueOnce(ok(updated));
+        const got = await setUserAdmin('u-1', true);
+        expect(got).toEqual(updated);
+        const init = fetchSpy.mock.calls[0][1] as RequestInit;
+        expect(init.method).toBe('PATCH');
+        expect(JSON.parse(init.body as string)).toEqual({ is_admin: true });
+    });
+
+    // ---- mangas + chapters ----
+
+    it('listAdminMangas GETs /v1/admin/mangas and forwards sync_state filter', async () => {
+        fetchSpy.mockResolvedValueOnce(
+            ok({ items: [mangaFixture], page: { limit: 100, offset: 0, total: 1 } })
+        );
+        const page = await listAdminMangas({ syncState: 'in_progress', limit: 100 });
+        expect(page.items[0].sync_state).toBe('synced');
+        const url = fetchSpy.mock.calls[0][0] as string;
+        expect(url).toContain('sync_state=in_progress');
+        expect(url).toContain('limit=100');
+    });
+
+    it('listAdminChapters GETs the nested chapter route and parses the paged envelope', async () => {
+        const chapter = {
+            id: 'c-1',
+            manga_id: 'm-1',
+            number: 1,
+            title: null,
+            page_count: 12,
+            created_at: '2026-01-01T00:00:00Z',
+            sync_state: 'synced' as const,
+            latest_seen_at: null
+        };
+        fetchSpy.mockResolvedValueOnce(
+            ok({ items: [chapter], page: { limit: 200, offset: 0, total: 1 } })
+        );
+        const resp = await listAdminChapters('m-1');
+        expect(resp.items).toEqual([chapter]);
+        expect(resp.page.total).toBe(1);
+        const url = fetchSpy.mock.calls[0][0] as string;
+        expect(url).toMatch(/\/v1\/admin\/mangas\/m-1\/chapters$/);
+    });
+
+    it('listAdminChapters forwards limit + offset query params', async () => {
+        fetchSpy.mockResolvedValueOnce(
+            ok({ items: [], page: { limit: 50, offset: 100, total: 0 } })
+        );
+        await listAdminChapters('m-1', { limit: 50, offset: 100 });
+        const url = fetchSpy.mock.calls[0][0] as string;
+        expect(url).toContain('limit=50');
+        expect(url).toContain('offset=100');
+    });
+
+    // ---- system ----
+
+    it('getSystemStats GETs /v1/admin/system and parses the four-key envelope', async () => {
+        fetchSpy.mockResolvedValueOnce(ok(systemFixture));
+        const s = await getSystemStats();
+        expect(s.disk?.percent_used).toBe(50);
+        expect(s.memory.percent_used).toBe(50);
+        expect(s.cpu.percent_used).toBe(12.3);
+        expect(s.alerts).toEqual([]);
+        const url = fetchSpy.mock.calls[0][0] as string;
+        expect(url).toMatch(/\/v1\/admin\/system$/);
+    });
+
+    it('getSystemStats keeps disk null when backend reports a non-local store', async () => {
+        fetchSpy.mockResolvedValueOnce(ok({ ...systemFixture, disk: null }));
+        const s = await getSystemStats();
+        expect(s.disk).toBeNull();
+    });
+
+    // ---- force resync ----
+
+    it('resyncManga POSTs to /v1/admin/mangas/{id}/resync and returns the envelope', async () => {
+        const resp = {
+            manga: {
+                id: 'm-1',
+                title: 'T',
+                status: 'ongoing',
+                alt_titles: [],
+                description: null,
+                cover_image_path: 'mangas/m-1/cover.jpg',
+                created_at: '2026-01-01T00:00:00Z',
+                updated_at: '2026-01-02T00:00:00Z',
+                authors: [],
+                genres: [],
+                tags: []
+            },
+            metadata_status: 'updated',
+            cover_fetched: true
+        };
+        fetchSpy.mockResolvedValueOnce(ok(resp));
+        const got = await resyncManga('m-1');
+        expect(got.metadata_status).toBe('updated');
+        expect(got.cover_fetched).toBe(true);
+        expect(got.manga.id).toBe('m-1');
+        const url = fetchSpy.mock.calls[0][0] as string;
+        expect(url).toMatch(/\/v1\/admin\/mangas\/m-1\/resync$/);
+        const init = fetchSpy.mock.calls[0][1] as RequestInit;
+        expect(init.method).toBe('POST');
+    });
+
+    it('resyncManga surfaces 503 service_unavailable when the daemon is off', async () => {
+        fetchSpy.mockResolvedValueOnce(
+            envelope(503, 'service_unavailable', 'crawler daemon is disabled')
+        );
+        await expect(resyncManga('m-1')).rejects.toMatchObject({
+            status: 503,
+            code: 'service_unavailable'
+        });
+    });
+
+    it('resyncChapter POSTs to /v1/admin/chapters/{id}/resync and returns the envelope', async () => {
+        const resp = {
+            chapter: {
+                id: 'c-1',
+                manga_id: 'm-1',
+                number: 1,
+                title: 'Foo',
+                page_count: 7,
+                created_at: '2026-01-01T00:00:00Z'
+            },
+            outcome: 'fetched',
+            pages: 7
+        };
+        fetchSpy.mockResolvedValueOnce(ok(resp));
+        const got = await resyncChapter('c-1');
+        expect(got.outcome).toBe('fetched');
+        expect(got.pages).toBe(7);
+        expect(got.chapter.page_count).toBe(7);
+        const url = fetchSpy.mock.calls[0][0] as string;
+        expect(url).toMatch(/\/v1\/admin\/chapters\/c-1\/resync$/);
+        const init = fetchSpy.mock.calls[0][1] as RequestInit;
+        expect(init.method).toBe('POST');
+    });
+
+    it('resyncChapter handles the "skipped" outcome envelope', async () => {
+        const resp = {
+            chapter: {
+                id: 'c-1',
+                manga_id: 'm-1',
+                number: 1,
+                title: null,
+                page_count: 7,
+                created_at: '2026-01-01T00:00:00Z'
+            },
+            outcome: 'skipped',
+            pages: null
+        };
+        fetchSpy.mockResolvedValueOnce(ok(resp));
+        const got = await resyncChapter('c-1');
+        expect(got.outcome).toBe('skipped');
+        expect(got.pages).toBeNull();
+    });
+});

frontend/src/lib/api/admin.ts

@@ -0,0 +1,216 @@
+// Admin-only API client. Every endpoint here is guarded by
+// RequireAdmin on the backend (session cookie only — bearer tokens
+// won't reach these routes). 403s thrown here propagate up to the
+// /admin layout, which renders the framework error page.
+
+import { request, type Page } from './client';
+import type { User } from './auth';
+import type { MangaDetail } from './mangas';
+import type { Chapter } from './chapters';
+
+// ---- users -----------------------------------------------------------------
+
+export type AdminUsersPage = {
+    items: User[];
+    page: Page;
+};
+
+export type ListAdminUsersOptions = {
+    search?: string;
+    limit?: number;
+    offset?: number;
+};
+
+export async function listAdminUsers(
+    opts: ListAdminUsersOptions = {}
+): Promise<AdminUsersPage> {
+    const params = new URLSearchParams();
+    if (opts.search) params.set('search', opts.search);
+    if (opts.limit != null) params.set('limit', String(opts.limit));
+    if (opts.offset != null) params.set('offset', String(opts.offset));
+    const qs = params.toString();
+    return request<AdminUsersPage>(`/v1/admin/users${qs ? `?${qs}` : ''}`);
+}
+
+export async function deleteAdminUser(id: string): Promise<void> {
+    await request<void>(`/v1/admin/users/${encodeURIComponent(id)}`, {
+        method: 'DELETE'
+    });
+}
+
+export async function setUserAdmin(id: string, isAdmin: boolean): Promise<User> {
+    return request<User>(`/v1/admin/users/${encodeURIComponent(id)}`, {
+        method: 'PATCH',
+        headers: { 'content-type': 'application/json' },
+        body: JSON.stringify({ is_admin: isAdmin })
+    });
+}
+
+export type CreateAdminUserInput = {
+    username: string;
+    password: string;
+    is_admin?: boolean;
+};
+
+/** POST /v1/admin/users — admin-initiated account creation. Works
+ *  regardless of the ALLOW_SELF_REGISTER toggle, since the entire
+ *  point is for an admin to enroll someone when self-register is off. */
+export async function createAdminUser(input: CreateAdminUserInput): Promise<User> {
+    return request<User>('/v1/admin/users', {
+        method: 'POST',
+        headers: { 'content-type': 'application/json' },
+        body: JSON.stringify(input)
+    });
+}
+
+// ---- mangas / chapters with sync state -------------------------------------
+
+export type MangaSyncState = 'in_progress' | 'dropped' | 'synced';
+
+export type AdminMangaRow = {
+    id: string;
+    title: string;
+    status: string;
+    cover_image_path: string | null;
+    created_at: string;
+    updated_at: string;
+    sync_state: MangaSyncState;
+    chapter_count: number;
+    latest_seen_at: string | null;
+};
+
+export type AdminMangasPage = {
+    items: AdminMangaRow[];
+    page: Page;
+};
+
+export type ListAdminMangasOptions = {
+    search?: string;
+    syncState?: MangaSyncState;
+    limit?: number;
+    offset?: number;
+};
+
+export async function listAdminMangas(
+    opts: ListAdminMangasOptions = {}
+): Promise<AdminMangasPage> {
+    const params = new URLSearchParams();
+    if (opts.search) params.set('search', opts.search);
+    if (opts.syncState) params.set('sync_state', opts.syncState);
+    if (opts.limit != null) params.set('limit', String(opts.limit));
+    if (opts.offset != null) params.set('offset', String(opts.offset));
+    const qs = params.toString();
+    return request<AdminMangasPage>(`/v1/admin/mangas${qs ? `?${qs}` : ''}`);
+}
+
+export type ChapterSyncState =
+    | 'downloading'
+    | 'dropped'
+    | 'failed'
+    | 'not_downloaded'
+    | 'synced';
+
+export type AdminChapterRow = {
+    id: string;
+    manga_id: string;
+    number: number;
+    title: string | null;
+    page_count: number;
+    created_at: string;
+    sync_state: ChapterSyncState;
+    latest_seen_at: string | null;
+};
+
+export type AdminChaptersPage = {
+    items: AdminChapterRow[];
+    page: Page;
+};
+
+export type ListAdminChaptersOptions = {
+    limit?: number;
+    offset?: number;
+};
+
+export async function listAdminChapters(
+    mangaId: string,
+    opts: ListAdminChaptersOptions = {}
+): Promise<AdminChaptersPage> {
+    const params = new URLSearchParams();
+    if (opts.limit != null) params.set('limit', String(opts.limit));
+    if (opts.offset != null) params.set('offset', String(opts.offset));
+    const qs = params.toString();
+    return request<AdminChaptersPage>(
+        `/v1/admin/mangas/${encodeURIComponent(mangaId)}/chapters${qs ? `?${qs}` : ''}`
+    );
+}
+
+// ---- system ----------------------------------------------------------------
+
+export type DiskStats = {
+    total_bytes: number;
+    used_bytes: number;
+    free_bytes: number;
+    percent_used: number;
+};
+
+export type MemoryStats = {
+    total_bytes: number;
+    used_bytes: number;
+    percent_used: number;
+};
+
+export type CpuStats = {
+    percent_used: number;
+};
+
+export type Alert = {
+    level: 'warning';
+    message: string;
+};
+
+export type SystemStats = {
+    disk: DiskStats | null;
+    memory: MemoryStats;
+    cpu: CpuStats;
+    alerts: Alert[];
+};
+
+export async function getSystemStats(): Promise<SystemStats> {
+    return request<SystemStats>('/v1/admin/system');
+}
+
+// ---- force resync ----------------------------------------------------------
+
+export type MangaResyncResponse = {
+    manga: MangaDetail;
+    metadata_status: 'new' | 'updated' | 'unchanged';
+    cover_fetched: boolean;
+};
+
+export type ChapterResyncResponse = {
+    chapter: Chapter;
+    outcome: 'fetched' | 'skipped';
+    /** Page count when `outcome === 'fetched'`; null when skipped. */
+    pages: number | null;
+};
+
+/** POST /v1/admin/mangas/:id/resync — refetches metadata + cover from
+ *  the manga's live crawler source. Long-running (one HTTP request per
+ *  Chromium nav + image download), so the UI should disable the trigger
+ *  and surface progress. */
+export async function resyncManga(id: string): Promise<MangaResyncResponse> {
+    return request<MangaResyncResponse>(
+        `/v1/admin/mangas/${encodeURIComponent(id)}/resync`,
+        { method: 'POST' }
+    );
+}
+
+/** POST /v1/admin/chapters/:id/resync — force-refetches a chapter's
+ *  pages even if `page_count > 0`. Same long-running caveat as
+ *  `resyncManga`. */
+export async function resyncChapter(id: string): Promise<ChapterResyncResponse> {
+    return request<ChapterResyncResponse>(
+        `/v1/admin/chapters/${encodeURIComponent(id)}/resync`,
+        { method: 'POST' }
+    );
+}

frontend/src/lib/api/auth.test.ts

@@ -14,7 +14,8 @@ import {
     me,
     changePassword,
     createToken,
-    deleteToken
+    deleteToken,
+    getAuthConfig
 } from './auth';
 
 function ok(body: unknown, status = 200): Response {
@@ -94,6 +95,11 @@ describe('auth api client', () => {
         expect(url).toMatch(/\/v1\/auth\/logout$/);
         const init = fetchSpy.mock.calls[0][1] as RequestInit;
         expect(init.method).toBe('POST');
+        // Consistent content-type for all mutation requests, matching
+        // the rest of the module — axum doesn't require it but the
+        // header keeps the request style uniform.
+        const headers = new Headers(init.headers);
+        expect(headers.get('content-type')).toBe('application/json');
     });
 
     it('me returns the user on 200', async () => {
@@ -164,6 +170,17 @@ describe('auth api client', () => {
         expect(url).toMatch(/\/v1\/auth\/tokens$/);
     });
 
+    it('getAuthConfig GETs /v1/auth/config and parses the flag', async () => {
+        fetchSpy.mockResolvedValueOnce(ok({ self_register_enabled: false }));
+        const cfg = await getAuthConfig();
+        expect(cfg.self_register_enabled).toBe(false);
+        const url = fetchSpy.mock.calls[0][0] as string;
+        expect(url).toMatch(/\/v1\/auth\/config$/);
+        const init = fetchSpy.mock.calls[0][1] as RequestInit;
+        // Public endpoint; no method override means default GET.
+        expect(init?.method ?? 'GET').toBe('GET');
+    });
+
     it('deleteToken DELETEs to /v1/auth/tokens/{id} and handles 204', async () => {
         fetchSpy.mockResolvedValueOnce(noContent());
         await expect(deleteToken('t1')).resolves.toBeUndefined();

frontend/src/lib/api/auth.ts

@@ -4,6 +4,7 @@ export type User = {
     id: string;
     username: string;
     created_at: string;
+    is_admin: boolean;
 };
 
 export type Credentials = {
@@ -32,7 +33,14 @@ export async function login(creds: Credentials): Promise<User> {
 }
 
 export async function logout(): Promise<void> {
-    await request<void>('/v1/auth/logout', { method: 'POST' });
+    await request<void>('/v1/auth/logout', {
+        method: 'POST',
+        // Consistent with the other POST/PATCH helpers in this module.
+        // axum doesn't require it (no body), but keeping the header
+        // on every mutation request avoids the false-flag in logs and
+        // matches the project's style.
+        headers: { 'content-type': 'application/json' }
+    });
 }
 
 export type ChangePassword = {
@@ -92,3 +100,19 @@ export async function createToken(name: string): Promise<CreatedToken> {
 export async function deleteToken(id: string): Promise<void> {
     await request<void>(`/v1/auth/tokens/${encodeURIComponent(id)}`, { method: 'DELETE' });
 }
+
+export type AuthConfig = {
+    /** Effective value (`allow_self_register && !private_mode`).
+     * When false, /v1/auth/register returns 403 and the UI should
+     * hide its register affordance. Admins can still mint accounts
+     * via POST /v1/admin/users. */
+    self_register_enabled: boolean;
+    /** When true, every read endpoint requires auth and anonymous
+     * visitors are redirected to `/login` (see `+layout.ts`). */
+    private_mode: boolean;
+};
+
+/** Public — no auth, no cookie required. */
+export async function getAuthConfig(): Promise<AuthConfig> {
+    return request<AuthConfig>('/v1/auth/config');
+}

frontend/src/lib/api/chapters.test.ts

@@ -11,7 +11,8 @@ import {
     listChapters,
     getChapter,
     getChapterPages,
-    createChapter
+    createChapter,
+    chapterLabel
 } from './chapters';
 
 function ok(body: unknown): Response {
@@ -129,6 +130,18 @@ describe('chapters api client', () => {
         }
     });
 
+    describe('chapterLabel', () => {
+        it('returns the site title verbatim when present', () => {
+            expect(chapterLabel({ number: 7, title: 'Ch.7 : Official' })).toBe(
+                'Ch.7 : Official'
+            );
+        });
+
+        it('falls back to "Chapter {number}" when title is null', () => {
+            expect(chapterLabel({ number: 3, title: null })).toBe('Chapter 3');
+        });
+    });
+
     it('getChapterPages unwraps the {pages} envelope into the array', async () => {
         fetchSpy.mockResolvedValueOnce(
             ok({

frontend/src/lib/api/chapters.ts

@@ -14,6 +14,10 @@ export type ChaptersPage = {
     page: Page;
 };
 
+export function chapterLabel(c: Pick<Chapter, 'number' | 'title'>): string {
+    return c.title ?? `Chapter ${c.number}`;
+}
+
 export type ListOptions = {
     limit?: number;
     offset?: number;

frontend/src/lib/api/client.test.ts

@@ -1,5 +1,5 @@
 import { describe, it, expect, vi, beforeEach, afterEach, type MockInstance } from 'vitest';
-import { ApiError, request } from './client';
+import { ApiError, request, setOn401Hook } from './client';
 import { getManga } from './mangas';
 
 describe('request error envelope parsing', () => {
@@ -73,3 +73,88 @@ describe('request error envelope parsing', () => {
         expect(err.code).toBe('http_error');
     });
 });
+
+describe('on401 hook', () => {
+    let fetchSpy: MockInstance<typeof globalThis.fetch>;
+
+    beforeEach(() => {
+        fetchSpy = vi.spyOn(globalThis, 'fetch');
+    });
+    afterEach(() => {
+        vi.restoreAllMocks();
+        // Critical: reset the module-level hook between tests so a
+        // hook installed by one test doesn't leak into the next.
+        setOn401Hook(null);
+    });
+
+    it('invokes the hook exactly once on a 401 response and re-throws', async () => {
+        const hook = vi.fn();
+        setOn401Hook(hook);
+        fetchSpy.mockResolvedValueOnce(
+            new Response(
+                JSON.stringify({ error: { code: 'unauthenticated', message: 'no auth' } }),
+                { status: 401, headers: { 'content-type': 'application/json' } }
+            )
+        );
+        await expect(getManga('x')).rejects.toMatchObject({
+            status: 401,
+            code: 'unauthenticated'
+        });
+        expect(hook).toHaveBeenCalledTimes(1);
+    });
+
+    it('does not invoke the hook on non-401 errors', async () => {
+        const hook = vi.fn();
+        setOn401Hook(hook);
+        fetchSpy.mockResolvedValueOnce(
+            new Response(
+                JSON.stringify({ error: { code: 'not_found', message: 'no' } }),
+                { status: 404, headers: { 'content-type': 'application/json' } }
+            )
+        );
+        await expect(getManga('x')).rejects.toMatchObject({ status: 404 });
+        expect(hook).not.toHaveBeenCalled();
+    });
+
+    it('does not invoke the hook on successful responses', async () => {
+        const hook = vi.fn();
+        setOn401Hook(hook);
+        fetchSpy.mockResolvedValueOnce(
+            new Response(
+                JSON.stringify({
+                    id: 'm1',
+                    title: 't',
+                    status: 'ongoing',
+                    alt_titles: [],
+                    description: null,
+                    cover_image_path: null,
+                    created_at: '2026-01-01T00:00:00Z',
+                    updated_at: '2026-01-01T00:00:00Z',
+                    authors: [],
+                    genres: [],
+                    tags: []
+                }),
+                { status: 200, headers: { 'content-type': 'application/json' } }
+            )
+        );
+        await getManga('m1');
+        expect(hook).not.toHaveBeenCalled();
+    });
+
+    it('swallows hook exceptions so the original ApiError still propagates', async () => {
+        const consoleSpy = vi.spyOn(console, 'error').mockImplementation(() => {});
+        setOn401Hook(() => {
+            throw new Error('hook boom');
+        });
+        fetchSpy.mockResolvedValueOnce(
+            new Response(
+                JSON.stringify({ error: { code: 'unauthenticated', message: 'x' } }),
+                { status: 401, headers: { 'content-type': 'application/json' } }
+            )
+        );
+        await expect(getManga('x')).rejects.toMatchObject({ status: 401 });
+        // The original ApiError won — the hook's panic was logged but
+        // didn't replace the API error.
+        expect(consoleSpy).toHaveBeenCalled();
+    });
+});

frontend/src/lib/api/client.ts

@@ -25,6 +25,21 @@ export class ApiError extends Error {
 
 type ErrorEnvelope = { error?: { code?: unknown; message?: unknown } };
 
+/**
+ * Optional hook fired the first moment `request()` observes a 401 on
+ * any endpoint. Used by the session store to clear the cached user
+ * when the server reports the session is no longer valid (expired
+ * cookie, rotated server-side, password changed on another device).
+ *
+ * Set to `null` (or `undefined`) to disable. Tests that don't want
+ * the side effect should leave it unset.
+ */
+let on401Hook: (() => void) | null = null;
+
+export function setOn401Hook(handler: (() => void) | null): void {
+    on401Hook = handler;
+}
+
 export async function request<T>(path: string, init?: RequestInit): Promise<T> {
     // Forward credentials (session cookie) explicitly so cross-origin
     // deployments — those configured via CORS_ALLOWED_ORIGINS — keep
@@ -54,6 +69,16 @@ export async function request<T>(path: string, init?: RequestInit): Promise<T> {
         } catch {
             // Body wasn't parseable; keep the http_error fallback.
         }
+        if (res.status === 401 && on401Hook) {
+            // Fire before throwing so the session store updates even
+            // if the caller swallows the ApiError (e.g. the *OrEmpty
+            // wrappers used by guest-rendering pages).
+            try {
+                on401Hook();
+            } catch (e) {
+                console.error('on401 hook threw:', e);
+            }
+        }
         throw new ApiError(res.status, code, message);
     }
     // Any empty body (not just 204) returns undefined — the manga-add

frontend/src/lib/auth-config.svelte.ts

@@ -0,0 +1,49 @@
+// Anonymous-relevant auth policy (currently just whether self-
+// registration is enabled). Loaded once per browser session on root-
+// layout mount, then read reactively from `authConfig.self_register_enabled`.
+//
+// Defaults to `self_register_enabled = true` while loading so the
+// register link doesn't flash off-and-on for the default-open case.
+// If the fetch fails (network blip, backend restart), the stale value
+// is kept — there's no per-request retry. A new tab will retry on its
+// own mount.
+//
+// Same browser-only contract as `session.svelte.ts` — see that file's
+// SSR comment.
+
+import { browser } from '$app/environment';
+import { getAuthConfig } from './api/auth';
+
+class AuthConfigStore {
+    self_register_enabled = $state(true);
+    private_mode = $state(false);
+    loaded = $state(false);
+    private loading = false;
+
+    async load(): Promise<void> {
+        if (this.loaded || this.loading || !browser) return;
+        this.loading = true;
+        try {
+            const cfg = await getAuthConfig();
+            this.self_register_enabled = cfg.self_register_enabled;
+            this.private_mode = cfg.private_mode;
+            this.loaded = true;
+        } catch {
+            // Keep optimistic default; next page mount will retry.
+        } finally {
+            this.loading = false;
+        }
+    }
+
+    /** Seed from server-rendered layout data so the very first paint
+     *  doesn't flash the loading state. Used by `+layout.ts` /
+     *  `+layout.svelte` on the universal-load path. Safe to call from
+     *  SSR (no `browser` guard) since it touches only reactive state. */
+    seed(cfg: { self_register_enabled: boolean; private_mode: boolean }): void {
+        this.self_register_enabled = cfg.self_register_enabled;
+        this.private_mode = cfg.private_mode;
+        this.loaded = true;
+    }
+}
+
+export const authConfig = new AuthConfigStore();

frontend/src/lib/components/Pager.svelte

@@ -0,0 +1,128 @@
+<script lang="ts">
+    type Props = {
+        page: number;
+        totalPages: number;
+        onChange: (page: number) => void;
+        testid?: string;
+    };
+
+    let { page, totalPages, onChange, testid }: Props = $props();
+
+    type Slot = number | 'ellipsis';
+
+    // Compact layout: always show first + last, surround the current page with
+    // its direct neighbours, and use "…" to elide the rest. Keeps the bar to
+    // at most 7 buttons regardless of totalPages.
+    function buildSlots(p: number, total: number): Slot[] {
+        if (total <= 7) {
+            return Array.from({ length: total }, (_, i) => i + 1);
+        }
+        const out: Slot[] = [1];
+        if (p <= 4) {
+            for (let i = 2; i <= 5; i++) out.push(i);
+            out.push('ellipsis');
+            out.push(total);
+        } else if (p >= total - 3) {
+            out.push('ellipsis');
+            for (let i = total - 4; i <= total; i++) out.push(i);
+        } else {
+            out.push('ellipsis');
+            out.push(p - 1);
+            out.push(p);
+            out.push(p + 1);
+            out.push('ellipsis');
+            out.push(total);
+        }
+        return out;
+    }
+
+    const slots = $derived(buildSlots(page, totalPages));
+</script>
+
+{#if totalPages > 1}
+    <nav class="pager" aria-label="Pagination" data-testid={testid}>
+        <button
+            type="button"
+            class="step"
+            disabled={page <= 1}
+            onclick={() => onChange(page - 1)}
+            aria-label="Previous page"
+        >
+            ‹ Prev
+        </button>
+
+        {#each slots as slot, i (i)}
+            {#if slot === 'ellipsis'}
+                <span class="ellipsis" aria-hidden="true">…</span>
+            {:else}
+                <button
+                    type="button"
+                    class="num"
+                    class:active={slot === page}
+                    aria-current={slot === page ? 'page' : undefined}
+                    aria-label={`Go to page ${slot}`}
+                    onclick={() => onChange(slot)}
+                >
+                    {slot}
+                </button>
+            {/if}
+        {/each}
+
+        <button
+            type="button"
+            class="step"
+            disabled={page >= totalPages}
+            onclick={() => onChange(page + 1)}
+            aria-label="Next page"
+        >
+            Next ›
+        </button>
+    </nav>
+{/if}
+
+<style>
+    .pager {
+        display: flex;
+        flex-wrap: wrap;
+        align-items: center;
+        gap: var(--space-1);
+        margin: var(--space-4) 0;
+        justify-content: center;
+    }
+
+    .step,
+    .num {
+        min-width: 36px;
+        height: 36px;
+        padding: 0 var(--space-2);
+        background: var(--surface);
+        border: 1px solid var(--border);
+        border-radius: var(--radius-md);
+        color: var(--text);
+        cursor: pointer;
+        font-size: var(--font-sm);
+    }
+
+    .step:hover:not(:disabled),
+    .num:hover:not(.active) {
+        border-color: var(--primary);
+    }
+
+    .step:disabled {
+        opacity: 0.4;
+        cursor: not-allowed;
+    }
+
+    .num.active {
+        background: var(--primary);
+        color: var(--primary-contrast);
+        border-color: var(--primary);
+        cursor: default;
+    }
+
+    .ellipsis {
+        padding: 0 var(--space-1);
+        color: var(--text-muted);
+        user-select: none;
+    }
+</style>