[husthunterpy01]

Problem

The backend CI "Check convention" step failed on main with 16 UP017 errors ("use datetime.UTC alias"). The scrapers CI runs the same unpinned ruff check . and fails the same way.

CI installs the latest ruff each run. Ruff 0.17.0 assumes a newer Python when the project does not say which one it targets, and now suggests datetime.UTC. That alias only exists in Python 3.11+, and both the backend and the scrapers run on Python 3.10 (CI and the Docker image), so applying the "fix" would break the app.

Fix

Add backend/ruff.toml and scrapers/ruff.toml with target-version = "py310", so ruff judges the code against the Python it actually runs on. No application code changes.

Testing

• Reproduced the 16 backend errors with ruff 0.17.0, then checked that ruff check . passes in backend/ and in scrapers/ with both 0.17.0 and 0.16.7.

Note

The workflows still run an unpinned pip install ruff, so a future release can add new rules and fail CI again without any code change. Pinning the version (for example ruff==0.17.0) would prevent that; left out here to keep the fix minimal.