TaskHost.tsx used a literal NUL as the delimiter in its drag-and-drop
payload, and tools/dict/build.mjs used one to join headword and part of
speech. Both work at runtime. Both also make the file *binary* to every
text tool: git shows "Bin 12259 bytes" instead of a diff, and grep prints
nothing at all for a match.
That is not hypothetical. Searching TaskHost.tsx for "<input" came back
empty three times while reviewing it, which is how its four exercise
inputs came to be reported as absent -- and why the accessibility defect
in them went unseen. Written as the escape \u0000 the value is identical
and the file stays text.
test/source-hygiene.test.ts fails on any control byte in a source file, so
this cannot come back quietly.
With the files readable again, the sweep the NUL had been hiding: eleven
form controls had no accessible name. The exercise blanks announced only
an ellipsis, and the part-of-speech select announced nothing. A
placeholder is not a label -- it disappears the moment you type. All
eleven now carry one, named after the thing they answer.
`npm run lint` gains --max-warnings 0. exhaustive-deps is configured as a
warning, so a hooks-dependency bug would have passed CI silently.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The seed pre-marked the artifact's 30 headwords secure on first run. Two
reasons it is gone rather than merely disabled:
It was never 30 cards. The match was on headword, and homographs each
carry their own lemma, so 그 as pronoun and as determiner both matched —
47 rows for a 30-word list.
Worse, "Reset everything" deleted the cards and then deleted the
'seed.known' guard along with the other meta keys, so the next boot
re-seeded and the deck looked untouched. The one thing a wipe exists for,
undone by the wipe itself.
Migration 5 clears the seed from installs that already have it. seedCard()
is the only writer that leaves updated_at = 0 on a card and the seed was
its only caller, so `DELETE FROM card WHERE updated_at = 0` removes exactly
the seeded rows and nothing the learner graded — the timestamp rule paying
for itself a second time.
test/domain/reset.test.ts pins both scopes: what a full wipe must leave
empty, what a roadmap reset must keep, that the deletions are tombstoned
so a sync cannot restore them, and that migration 5 really runs against a
schema-4 database rather than the test performing the delete itself.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
POST /api/tutor takes the assembled system prompt, the transcript the
client owns, and the new message, and streams tokens back. It holds
nothing between requests, so a dropped connection costs one turn rather
than the conversation.
The seam moved first: Sample took the assembled prompt as messages[0] with
role user. It now has an explicit system field, which is what lets the
backend put it in the API's system parameter as a cached block. The gate
is ~12k characters and is byte-identical for as long as the learner stays
in one unit, so every turn after the first reads the prefix at a fraction
of the input price. That is the single biggest cost lever in the design,
and it was unreachable through the old shape.
prompt/tutor-system.md still ships unchanged; only where the string is
placed changed.
SSE has three rules that are silent when broken, and all three are
handled: every event ends with a blank line, payloads are JSON-encoded
because a raw newline in Korean text would break the framing, and a `:`
heartbeat every 15s keeps intermediaries from timing the stream out.
Cache-Control is set on the returned Response rather than inside
streamSSE, which writes its own and would overwrite it; `no-transform` is
there because compression, not buffering, is what usually makes SSE look
like it hangs behind a proxy.
The client uses fetch + getReader, not EventSource — EventSource cannot
POST, and the body is {system, history, message}. Aborting closes the
connection, the server aborts upstream, and a cancelled turn stops
billing. With no server configured the app falls back to the stub, so the
offline build is untouched.
backends/anthropic.ts is the default. backends/agent-sdk.ts is deliberately
unimplemented and documents why the plain API was chosen over PORT.md's
Agent SDK — chiefly that its prompt accepts only user-role messages, so
the transcript would have to be flattened into a single turn.
The endpoint's own tests use a mock backend and need no API key.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Hono and pg, run under --experimental-strip-types, so the deployed thing
is the source. GET /api/sync?cursor=N pages rows above the cursor;
POST /api/sync upserts last-write-wins. Bearer token on everything under
/api; /health is open, for the container healthcheck.
Rows are stored generically — primary key as text, body as JSONB —
because the server never reads inside a row. It stores and orders them and
the client interprets them, which keeps the two schemas from having to
move in lockstep.
change_seq is bumped by a BEFORE UPDATE trigger rather than by the write
path. A row edited after a client last pulled would otherwise keep its old
sequence, sit below that client's cursor, and never be delivered; putting
it in the database means no future write path can forget.
The last-write-wins comparison is in the ON CONFLICT clause itself, so a
losing row is not written at all and does not bump change_seq — a
conflict does not become traffic for every other device.
test/sync/roundtrip.test.ts runs two clients against a real Postgres and
asserts what actually goes wrong in sync: that a fresh client's seeded rows
cannot overwrite the server's history (the artifact's bug, as an executable
test), that a delete propagates, and that dict.loadedBands never crosses
the wire. It skips without HANKAN_TEST_SERVER, so npm test still runs
anywhere.
POST /api/test/reset exists only when HANKAN_TEST_MODE=1, so it cannot be
reached on the Pi even if the token leaks.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
React + Vite + TypeScript, PWA, offline-first. Six tabs: 수업 오늘 단어 문장
문법 한글, plus the full-screen SRS review overlay, the reading drill, the
conjugation trainer and the 두벌식 keyboard.
The visual language is carried over deliberately: two hand-tuned palettes,
three type stacks, about a dozen component classes, zero border-radius and
no icons anywhere — Korean glyphs do the work icons would.
THE GATE is the reason this app exists. buildGate() already took a
vocabQuery hook; filling it with a band query is what turns 371 hand-typed
words into something that scales. Three refinements sit inside that hook,
all of them narrowing:
1. words a not-yet-finished unit is the first to introduce are excluded,
so a frequency ceiling cannot smuggle 3.4's material into 2.1;
2. Phase 1 is filtered by the phonological ladder;
3. the list is capped at 800 by frequency, because renderGate() inlines
it into the prompt — strictly more restrictive than the band, so it
cannot leak.
prompt/tutor-system.md ships unchanged with {{GATE}} filled by renderGate().
Confidence is clamped per turn. The artifact wrote the model's ::progress
number straight into the sole gate on advancement, so one hallucinated 95
skipped a unit.
stub-tutor.ts stands in for the model on the artifact's exact contract —
onText receives cumulative text, an aborted turn keeps what it streamed —
so the real endpoint drops in without touching the UI. It rotates all four
task types and climbs progress gradually, which makes every render path
reachable with no server.
Two artifact bugs are not ported: task state lived in the full-page
re-render, so anything arriving mid-answer wiped typed text and placed
chips; and the day number was computed once at module load, so a session
left open overnight scheduled against yesterday.
Verified in a browser: all six tabs work, and after a hard reload with the
network cut every tab still works — including dictionary search out of OPFS.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Closes REVIEW.md §2. 167 of 371 roadmap words had no lexicon entry, so the
word rail silently showed nothing. Now:
Roadmap words: 371/371 resolve
Spiral targets: 35/35 resolve
Deck words: 386/386 resolve
and npm run dict:assert makes it a blocking build failure, not a silent
empty rail.
No runtime morphological analyser ships. lib/conjugation.js surfaceForms()
runs at BUILD time over every verb and adjective, so looking up a conjugated
form is an index hit on the surface table.
The frequency join had to be inverted. A subtitle frequency list holds
surface forms; a dictionary holds lemmas whose -다 citation form barely
occurs in running text, so joining on headword gives verbs a frequency of
roughly zero. Expanding each lemma into the forms it plausibly takes and
summing recovers 하다 from 118 to 89,041. Forms claimed by more than one
lemma are dropped rather than split, so homographs don't inherit each
other's mass. Those expansions score frequency only — the surface table
itself stays strictly surfaceForms() output plus the headword.
Bands are one per curriculum phase. Phase 1 admits no frequency band at
all: during the writing-system phase every word must be phonologically
legal for the unit reached, and a rank ceiling would hand the learner a
겹받침 during unit 1.4. shared/phonology.mjs lifts validate.mjs's own
feature ladder to enforce that; it agrees with the validator on all 371
words.
Sources are chosen automatically — KRDICT when vendored, otherwise the
kaikki.org extract. KRDICT's download is a JS form behind anti-bot
protection, so it cannot be fetched by CI; the derived band files are
committed instead, which the app needs offline regardless. Attribution and
the share-alike terms are in NOTICE.md.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Nothing above db/ knows which driver it got. sqlite.web.ts runs
@sqlite.org/sqlite-wasm in a dedicated Worker; sqlite.native.ts uses the
Capacitor plugin. Both apply the same migration array.
The web driver uses the OPFS SAHPool VFS rather than the plain opfs VFS:
the latter needs COOP/COEP cross-origin isolation headers, which neither a
static host nor the Capacitor webview reliably provides. Same storage,
fewer deployment constraints.
THE TIMESTAMP RULE. The artifact had a sync bug where a fresh device
stamped its own empty defaults as newer than the server's real history and
clobbered it. Three layers make that unrepresentable rather than merely
avoided:
1. updated_at INTEGER NOT NULL DEFAULT 0 on every syncable table, so
forgetting the column is the SAFE failure — a row that loses every
last-write-wins comparison, not one that wins them all.
2. writes.ts splits every mutation into seedX() (never stamps) and
editX() (always stamps), and is the only file allowed to read the clock.
3. An ESLint rule enforces that, and the conformance suite asserts a
freshly seeded database has no non-zero updated_at anywhere.
Two batching limits are sized for the platform we cannot test here: Android
links the system SQLite, historically capped at 999 bound parameters, while
sqlite-wasm allows 32766. A multi-row insert sized for the browser would
fail only on the phone, at first launch, loading the dictionary. Both the
band insert and the word-rail lookup batch under the smaller ceiling, and
test/db/limits.test.ts fails at 3600 if that regresses.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
lib/ ships unchanged, so its types live in types/lib/ and are wired up by a
tsconfig path mapping. Adding types costs nothing; reimplementing the logic
would cost the two things that make this port possible.
The tests exist so a later refactor cannot silently drift them:
hangul the nine Composer cases named in the export README —
먹어 · 왔어 · 읽어 · 괜찮아 · 값 · 의사 · 뭐야 and backspace
conjugation all seven irregular classes, and every form in
IRREGULAR_FORMS reachable through haeche()
srs the SM-2 transitions, ease and interval clamps
blocks parse → answerText round-trip for all four task types
101 tests.
One is a pinned defect rather than a guarantee. blocks.parse() never closes
a ::gloss block on its "=" line, so a multi-sentence gloss — which the tutor
prompt explicitly invites — collapses into one run-on line keeping only the
last translation. lib/ ships unchanged, so the test records the real
behaviour and the app works around it at the call site.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
