Lint and Type-Check

1. uv run ruff check src

   — lint the code

2. uv run ruff format --check src

   — verify formatting

3. uv run pyrefly check src

   — static type analysis

Pyrefly + Django gotchas

django-stubs

# type: ignore

• Reverse relations (

  user.order_set

  ,

  author.article_set

  ) are not supported. This is a known pyrefly limitation, not a real bug. The right fix is to query the child model directly from its repository (

  OrderRepository().list_for_user(user_id)

  ) — push the access down into the repo layer rather than suppressing it. Only if that's impossible, narrow it with

  # type: ignore[attr-defined]

  at a single call site.

• ManyRelatedManager

  is generic over

  [Parent, Model]

  , not the concrete child. Don't rely on pyrefly to catch a mistyped M2M target — cover it with a test instead.
• Chained QuerySet methods beyond

  .all()

  are thinly typed. Keep chains inside the repository where the return type is an annotated

  list[SomeDTO]

  ; don't let querysets leak out into services.