siftlode/docs/development.md

Development

How to run Siftlode locally and pass the gate. Conventions for the backend code itself live in backend/app/README.md.

Node

One major, everywhere. .nvmrc pins it; the Dockerfile's frontend build stage, frontend/package.json's engines and @types/node must all match it — and so must the machine you run the gate on. frontend/src/lib/nodeEngine.contract.test.ts fails the gate the moment any of them drift apart, including when yours is the odd one out. nvm use in the repo root picks it up.

This is a contract, not a preference: tsc and vitest read the engine's own Intl and web APIs, and those change between majors — the same currency format renders $160M on one and $160.0M on the next. A gate that is green on a major you do not ship is green about nothing.

Run it locally

The whole stack (Postgres + API + worker) comes up from the base compose file plus the localdev override:

docker compose -f docker-compose.yml -f docker-compose.localdev.yml up --build

Browse at http://localhost:8080 (Google login works — the OAuth redirect is http://localhost:8080/auth/callback). The API runs alembic upgrade head on startup, so the schema is always current.

For a fast frontend edit loop, run the Vite dev server with HMR against that API:

cd frontend && npm install && npm run dev   # http://localhost:5173, proxying the API on :8080

The dev server also serves the design lab at http://localhost:5173/design-lab: the open design decisions and the chosen patterns, rendered with the app's real CSS. It never reaches a production build (see DESIGN.md).

The gate

A change is done when this is green, from the repo root:

bash scripts/check.sh        # every lane
bash scripts/check.sh lint   # the static lanes only (no tests, build or audits) — the quick loop
bash scripts/check.sh --brief          # either mode: one line per lane, output only for a red one
bash scripts/lint-changed.sh           # ruff + eslint + prettier on the uncommitted files only

It runs every lane even after one fails and names each red one at the end. lint-changed.sh is a convenience, not the gate; with --hook it doubles as a Claude Code Stop hook (silent when clean, the findings handed back otherwise).

The codebase's health numbers — size, complexity, test ratio, gate weight, comment noise — come from python scripts/audit_metrics.py (seconds; it reports, it never fails). --speed adds the speed baseline (frontend/e2e/speed.measure.ts: the feed's first card and a shared /watch link's time-to-play against the :8080 stack, with E2E_PASSWORD set). An epic that changes structure compares its before and after. What it runs, and why each lane runs where it does, is in the script's comments; frontend/src/lib/gates.contract.test.ts holds its lines, so a lane dropped or narrowed there fails a test. What each gate deliberately does NOT check — and why — is the gate register. There is no CI: the gate runs here, and a release runs it (plus e2e and the CVE scan) before anything is merged.

The lanes, for running one by hand:

Backend

# lint + format check (ruff is pinned in backend/requirements-dev.txt)
python -m ruff check --config backend/ruff.toml backend scripts
python -m ruff format --check --config backend/ruff.toml backend scripts

# type check — in the test image (requirements.lock does not install on Windows); new errors only,
# the pre-existing ones are in backend/.basedpyright/baseline.json
docker compose -f backend/docker-compose.test.yml run --rm --no-deps --build test \
  python -m basedpyright --project pyrightconfig.json

# tests — pure-logic + the DB-backed integration lane, against an ephemeral Postgres, ending with the
# coverage total. The backend tree is bind-mounted, so it always tests your working files.
docker compose -f backend/docker-compose.test.yml up --build --abort-on-container-exit --exit-code-from test
docker compose -f backend/docker-compose.test.yml down -v

# the lock against the advisory databases, at any severity
docker compose -f backend/docker-compose.test.yml run --rm --no-deps test \
  pip-audit -r requirements.lock --no-deps --disable-pip

A missing database or ffmpeg is a hard error, not a skip — so the gate can't print green while the DB-backed tests were quietly not run (SIFTLODE_TEST_REQUIRE_DB=0 is the explicit "pure-logic only" run for a machine without Postgres). Tests that need a database take the db fixture (backend/tests/conftest.py); the rest are pure-logic and run without one.

Frontend (from frontend/)

node ../scripts/check-node-modules.mjs   # node_modules == package-lock.json (else: npm ci)
npm run typecheck     # tsc x3 (app / node / e2e)
npm run lint          # eslint (typed rules included; warnings fail)
npm run format:check  # prettier
npm run knip          # unused files/exports/deps
npm run test          # vitest (incl. the compiler and gate-register contracts)
npx vite build        # the production bundle (devOnlyGuard fails it on dev-only code)
npm audit --omit=dev --audit-level=high   # what ships to the browser, at high or above

Coverage is reported, never enforced: npm run test -- --coverage, and the pytest lane's last line. The Playwright suite (npm run e2e) runs against the :8080 stack built from your tree; the release requires it. Before an image is pushed, it is scanned with Trivy (HIGH/CRITICAL with a fix fails; exceptions in .trivyignore.yaml, each with a reason and an expiry).

Branching

Trunk-based: branch off main, keep the branch gate-green, and land the whole change back to main in one reviewed step. Migrations are Alembic revisions under backend/alembic/versions; the API applies them on startup, and the DB-lane rebuilds the schema via alembic upgrade head, so a broken migration chain fails the tests.