ruff python-linting config-discovery release formatter

Ruff v0.10 stabilizes rules, improves version detection

v0.10 fixes config discovery to respect pyproject.toml requires-python without [tool.ruff] sections, stabilizes 20 lint rules, and hardens noqa comment parsing.

June 9, 2026

Summary

Config discovery changes eliminate silent fallbacks to Python 3.9 defaults; stricter noqa parsing catches typos that previously suppressed all rules. Both reduce hidden lint behavior drift in CI/CD.

Why it matters

Config discovery changes eliminate silent fallbacks to Python 3.9 defaults; stricter noqa parsing catches typos that previously suppressed all rules. Both reduce hidden lint behavior drift in CI/CD.

Implementation verdict

Drop-in upgrade for most users. Test noqa comments if you use unconventional formatting (malformed rule lists, trailing text after file-level suppressions). No breaking changes to linting output if already using explicit target-version. Worth upgrading now.

Sources

1.Ruff is an extremely fast Python linter and formatter, written in Rust
2.executing tens or hundreds of times faster than any individual tool
3.pyproject.toml files without a [tool.ruff] section would be ignored, including the requires-python setting
4.Ruff would then use the default Python version (3.9 as of this writing) instead
5.invalid syntax like ruff: noqa UP035 (missing colon after noqa) will now suppress all rules
6.It is now disallowed to have an invalid rule suffix in inline suppression comments

Dev Signal

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