Imported from kuhyx/todo-app (AGENTS.md). Install upstream with npx skills add kuhyx/todo-app. Copyright stays with the author.

CLAUDE.md — todo

Offline-first, CRDT-synced notes app. Flutter, targets Android + web.

The desktop app is the web build, served by a small local wrapper (bin/todo_desktop.dart) and shown in a Chrome --app window. Flutter's Linux embedder was removed: it manages only ~20fps at 4K while the same Dart code in Chrome sustains ~144fps. See docs/DOCS-desktop-performance-findings.md for the measurements. Do not re-add linux/ — flutter create --platforms linux would silently bring the slow path back. Capture an idea instantly (persisted on every keystroke), browse/filter notes, and sync peer-to-peer through a GitHub repo used as dumb storage.

• Package name: todo (Dart SDK ^3.12.2).
• Git remote: origin → github.com/kuhyx/todo-app.
• The note content also syncs to a separate private repo kuhyx/syncs (under todo-sync/) via the in-app GitHub sync (changeset files); that is data, not this codebase.

Git workflow (repo-specific — overrides global rules)

• Never open pull requests. Always commit and work directly on main and git push to origin/main. Do not create feature branches for normal work.
• End commit messages with the standard Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> trailer.

Commands

• Run tests + coverage: flutter test --coverage (suite runs in under a minute; keep it quick — see Testing below).
• Coverage summary: lcov --list coverage/lcov.info.
• Static analysis: flutter analyze (must be clean before committing).
• Format: dart format lib/ test/.
• Run the desktop app: ./run.sh (builds the web bundle, starts the wrapper, opens Chrome). Mobile: flutter run with a connected Android device.
• The wrapper serves on a fixed port 8730 with a fixed Chrome profile dir. Both must stay fixed: the GitHub token (localStorage) and the notes (IndexedDB) are keyed by origin and live in that profile, so changing either silently logs you out and hides your notes. Because the port cannot move, lib/desktop/port_guard.dart decides what to do when it is already taken: reap a wrapper with no window attached (so an upgrade can't leave you on old code), join one that still has a window, and refuse to touch anything else.
• Release APK: flutter build apk --release (signs with the debug key; debug builds are janky — always measure smoothness on a release build).
• Sync smoke test (hits real GitHub, needs a token): dart run tool/sync_smoke.dart.

Architecture

Three layers under lib/, each single-purpose:

• data/ — domain + local storage.
  • note.dart: Note model; Priority enum (low/medium/high, default medium, no "none"); Status enum (todo/inProgress/done/abandoned).
  • note_repository.dart: CRDT storage over sqlite_crdt. Schema is at version 3 with onCreate/onUpgrade migrations (v1→v2 adds the status column; v2→v3 backfills legacy priority 0→medium). Also defines NoteFilter (query / priorities / statuses / created+updated date ranges, AND-combined), NoteSort, watchNotes/watchCount streams, and importNotes (safe newer-wins merge by id).
• sync/ — GitHub-as-storage sync.
  • sync_service.dart: each device owns one file todo-sync/changesets/<nodeId>.json holding its full CRDT changeset. No two devices write the same file ⇒ no git merge conflicts; convergence is the CRDT layer's job (pull every other device's changeset and merge(), which is commutative + idempotent).
  • github_client.dart: thin GitHub contents-API client (injectable http.Client). github_device_auth.dart: OAuth device flow to mint a token. sync_settings.dart: persisted owner/repo/token/clientId.
  • notes_markdown.dart: round-trippable single-file export/import format (HTML-comment <!-- @note id=… priority=… status=… … --> markers).
• ui/ — screens, all take an injected NoteRepository.
  • capture_screen.dart: landing screen; always-focused text box pre-filled with the structured template; lazy note creation on first keystroke.
  • notes_list_screen.dart: list + search + sort + filter sheet + per-note sheet. Default view hides Done/Abandoned and shows no filter badge (looks unfiltered).
  • settings_screen.dart: GitHub connect/test, device-flow auth, and the Export/Import backup actions.
• main.dart: bootstrap only (// coverage:ignore-file) — wires platform DB paths and runApp.

Note template (default content of every new note)

lib/data/note_template.dart is the single source of truth — the stepper, the editor and the tests are all template-driven, so changing that list changes every surface. A new note pre-fills a title line plus what / where / must / done / verify / read first.

The set was cut from twelve sections to seven in 2026-07 after auditing 514 real sessions (docs/DOCS-llm-design-spec-audit.md): estimate, ask, nice, tech, never and depends were measurably never read, and verify was added because "test it yourself, on the phone" was the single most repeated correction in the corpus. Do not re-add a section without evidence that it gets used.

NoteTemplate.retiredLabels lists the dropped headings. parse() reports any note containing one as non-conforming so it opens in the raw editor — without that, the stepper would fold a retired section into its neighbour on the next save. tool/migrate_backlog.dart converts an old export (Settings → Export → migrate → Settings → Import).

Testing

• The suite must stay quick and fully green. It is currently 313 tests at 100% line coverage (2005 lines), running well under a minute on this machine. Don't regress either. (The "~5s" figure this file used to quote had drifted well before the port guard was added; measure before quoting a new one.)
• Widget tests use test/fake_note_repository.dart — a FakeNoteRepository built on StreamControllers, not a real DB. A real sqlite_crdt DB schedules timers that never drain under the widget tester's fake clock ("A Timer is still pending"); the fake avoids that.
• Pitfalls learned the hard way (keep following these):
  • Avoid pumpAndSettle when a widget animates forever — an autofocused TextField's cursor blink never settles, and an open device-code dialog keeps a pending poll timer. Use explicit pump(Duration) there. pumpAndSettle is fine once nothing is animating (e.g. a route/dialog pop, or a dialog already showing a static error).
  • Inject fakes rather than touching the platform: MockClient (package:http/testing.dart) for HTTP; the file_selector and url_launcher platform interfaces (MockPlatformInterfaceMixin) for the picker/launcher; stub SystemChannels.platform for clipboard.
  • To exercise the configured sync path, pass a MockClient via CaptureScreen(httpClient: …) / SettingsScreen(httpClient: …) — the real SyncService then runs without network.
  • getChangeset() serialises HLCs as String; merge() needs Hlc.parse and fresh mutable maps (QueryRows are read-only) — see the changeset test.
• Use // coverage:ignore-line / ignore-start/ignore-end only for genuinely unreachable code (e.g. a private static-only constructor, or a mobile-only Platform.isAndroid branch that can't run on the Linux test host), with a one-line reason.

Conventions

• Run dart format + flutter analyze (clean) before every commit.
• Comments explain intent/trade-offs, not syntax.
• Keep the app buttery-smooth and low on CPU/RAM — it's a quick-capture tool.
• Every file is at most 250 lines, source and prose alike. Enforced by a pre-commit hook (scripts/check_file_length.sh, delegating to the shared gate in ~/src/utils) and by .github/workflows/file-length.yml, so it fails the commit rather than being a note anyone can ignore. Install the hook on a fresh clone with scripts/install_hooks.sh.
• Only non-mutating checks go in .pre-commit-config.yaml. pre-commit stashes unstaged changes and restores them with git apply; a hook that rewrites a tracked file inside that window makes the restore conflict, which aborts the commit and drops the developer's uncommitted edit. That is why bump_patch_version.sh runs from the wrapper hook that install_hooks.sh writes, after pre-commit has exited and only when it passed — see the comments in both files. There is deliberately no baseline and no allowlist — split the file instead. Exemptions (generated, vendored, data files) live with the checker so the gate and the survey cannot disagree.
• Where a split would otherwise break callers, keep the original path as a barrel that re-exports the parts (note_template.dart, firebase_backend.dart, note_repository.dart all do this). Where a widget and its private State must stay one library, use part files (note_editor_*.dart, capture_screen_*.dart).

Flutter/Dart AI rules

Upstream's Flutter/Dart guidance used to be pasted in below this line, which made 85% of this always-loaded file a document nobody edits. It now lives in docs/, linked rather than inlined so the part loaded on every turn stays about this repo:

• Language, style and architecture
• State, routing and data
• Code generation, testing, theming and assets
• UI: theming, layout and overlays
• Colour, type, documentation and accessibility

Sourced from flutter/flutter docs/rules/rules.md via ~/.claude/CLAUDE.md's Flutter AI tooling setup. Re-fetch periodically.