CI runs the linter multiple times without any visible reason, using different versions of the tools and sometimes even different configurations. Perhaps a leftover from previous linters, the behaviour of which might have depended on the version of Python they run on?

Suggestions:

1. Run black/ruff/mypy only once, because the result should not depend on the platform or version of Python.
2. Run pre-commit instead of directly executing these tools, so that the same version and configuration are used locally on the programmers' machines when running pre-commit and during CI.
3. Specifically for these tools, move CI to pre-commit.ci instead of Azure, CircleCI or Github Actions.

As a first step towards this goal, I have tried to homogenize the versions of black/ruff/mypy, using recent versions:

• MNT Update ruff #30976
• MNT Fix pre-commit #31013
• MNT Update black and ruff config to match min Python version #31016
• MNT Update mypy #31018

This should address previous discussions on the subject:

• How to go about formatters and linters when contributing to the repo? #22546

Comments?