35390800c7
Two smaller operational items. POSTGRES 512M -> 1G. DATABASE_MAX_CONNECTIONS is 30 for a ~100-guest event (feed polling + SSE + uploads at once), and 30 backends plus Postgres 16's default shared_buffers leaves very little headroom at 512M. An OOM here doesn't degrade one feature -- every request path touches the database, so it takes the event down. Memory is the cheaper knob than shrinking the pool back and reintroducing the queueing it was raised to fix. .env.example now names the pairing explicitly, the way it already does for COMPRESSION_WORKER_CONCURRENCY. SOCIAL WRITES WERE UNTHROTTLED. toggle_like, add_comment and delete_comment were the only mutating endpoints in the app with no limit at all -- upload, join, recover, export and admin login all carry one. Asymmetric coverage rather than a deliberate decision. Low severity, and honestly so: a like fans an SSE broadcast to every client, but the export regeneration a comment deletion triggers is contained (REGEN_DEBOUNCE 20s, workers born with their epoch, superseded ones inert). So the ceiling is 120/min -- far above anything a real guest produces. This bounds a script, not an enthusiastic double-tapper. ONE bucket across all three actions: separate buckets would let a caller triple the aggregate write rate by alternating between them. Keyed per USER, matching the feed and upload limits -- at a venue every guest is behind one NAT, and an IP key is what made the /join and /feed limits turn guests away in the first place. Migration 020 seeds both keys, and both are wired into the admin allowlist, the config UI and the e2e reseed -- the step two earlier per-area toggles missed, which left switches that existed in code and could never be flipped. Tests: 4 e2e, including that the shared bucket really is shared (the part most likely to be lost in a refactor) and that one guest hitting the ceiling doesn't block another behind the same IP. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Migrations
SQLx-managed Postgres migrations. Each NNN_topic.up.sql has a matching
NNN_topic.down.sql. Run by sqlx::migrate!() at app start.
Rules
- Never edit a shipped migration. If a column needs to change or a fix needs to land, write a new migration. Production has already applied the old one and SQLx tracks each by checksum — editing in place will fail to apply on existing databases.
- Always pair
.up.sqlwith a.down.sql. Reverts may not be perfect (data loss is sometimes unavoidable) but the file must exist and do the best it can. - Prefer additive changes. New columns, new tables, new keys in
config. Drop / rename only when there is no alternative. - No business logic in migrations. Schema + seeds only. Anything that needs Rust code goes in a one-off binary, not a migration file.
- One concern per migration. Easier to revert. Easier to read in
git log.
Numbering
Zero-padded three digits, monotonically increasing. The next free number lives at the bottom of the directory listing — pick that.
Seed-only migrations
When you only need to add config keys (feature flags, defaults), use
INSERT … ON CONFLICT DO NOTHING so existing operator overrides survive. See
009_feature_toggles.up.sql for the canonical shape.