Two mistakes have recurred in this codebase: the hand-maintained schema in db/connection.py drifting from the Alembic chain, and a field quietly going missing from the hand-written mapping onto the plan response. Tests existed for individual instances of the second, written after each one was found. Both are now checked structurally. One test builds a database from the migrations and another from the hand-written schema and compares their real shape, ignoring cosmetic column ordering but failing on a missing column, wrong nullability, absent foreign key or index. The other walks the proposal dataclass and asserts every field reaches the response, so a field added later is covered without anyone remembering to extend the test. Anything deliberately kept off the wire goes in an explicit allow-list. Both were confirmed by breaking what they guard and watching them name it.
Backend — Föräldraledigplannerare
FastAPI + Python 3.14, packages managed with uv. Layered architecture
(entities → repositories → services → routers) with dependency injection so the
database backend (SQLite now, Postgres later) is swappable.
Setup
uv sync # install deps (incl. dev group)
uv run uvicorn app.main:app --reload # run dev server on :8000
uv run pytest # run tests with coverage
uv run ruff check . # lint
Layout
app/
config.py # pydantic-settings (app config + frozen LeaveRules)
dependencies.py # DI factories (pick repo impl by settings.database_type)
entities/ # plain dataclasses (domain)
models/ # pydantic API schemas
repositories/ # abstract interfaces
repositories_impl/ # concrete impls per backend (sqlite/, postgres/)
services/ # business logic
routers/ # FastAPI routes
db/connection.py # connection + (dev) schema bootstrap
utils/ # errors, logger
Demo data (manual/browser testing)
scripts/seed_demo.py seeds a realistic, ready-to-explore workspace through the
normal service/repository layers (no raw SQL) — a couple workspace with a
partner, a child born ~6 months ago, vacation rows for only some years (so the
is_assumed badge is visible), day overrides, and a spread of leave wishes
(fixed, flexible, and one deliberately underfunded to show a shortfall +
remedies + surplus advice). Login credentials are fixed and printed at the end.
uv run python scripts/seed_demo.py # create once; re-running is a no-op
uv run python scripts/seed_demo.py --reset # wipe the demo workspace and rebuild
Then open http://localhost:5173 and log in with the printed demo@example.com
credentials. Safe to re-run: without --reset it detects the existing demo
user and changes nothing; --reset only ever deletes the one demo workspace.
Reference vertical slice
VacationDays is implemented end-to-end (entity → schema → repo interface →
SQLite impl → service → router → tests). Copy this slice when adding a new
entity. See JUNIOR_ONBOARDING.md in the repo root for task-by-task guidance.
The inline schema in
db/connection.pyexists only so dev/tests are self-contained. Production schema is owned by Alembic migrations (a senior task).