Ruff 0.15.0 ڈاؤن لوڈ

Released on 2026-02-03.

Check out the blog post for a migration guide and overview of the changes!

Breaking changes
- Ruff now formats your code according to the 2026 style guide. See the formatter section below or in the blog post for a detailed list of changes.

- The linter now supports block suppression comments. For example, to suppress N803 for all parameters in this function:

```python
# ruff: disable[N803]
def foo(
legacyArg1,
legacyArg2,
legacyArg3,
legacyArg4,
): ...
# ruff: enable[N803]
```

See the documentation for more details.

- The `ruff:alpine` Docker image is now based on Alpine 3.23 (up from 3.21).

- The `ruff:debian` and `ruff:debian-slim` Docker images are now based on Debian 13 "Trixie" instead of Debian 12 "Bookworm."

- Binaries for the `ppc64` (64-bit big-endian PowerPC) architecture are no longer included in our releases. It should still be possible to build Ruff manually for this platform, if needed.

- Ruff now resolves all `extend`ed configuration files before falling back on a default Python version.

Stabilization
The following rules have been stabilized and are no longer in preview:

- `blocking-http-call-httpx-in-async-function` (ASYNC212)
- `blocking-path-method-in-async-function` (ASYNC240)
- `blocking-input-in-async-function` (ASYNC250)
- `map-without-explicit-strict` (B912)
- `if-exp-instead-of-or-operator` (FURB110)
- `single-item-membership-test` (FURB171)
- `missing-maxsplit-arg` (PLC0207)
- `unnecessary-lambda` (PLW0108)
- `unnecessary-empty-iterable-within-deque-call` (RUF037)
- `in-empty-collection` (RUF060)
- `legacy-form-pytest-raises` (RUF061)
- `non-octal-permissions` (RUF064)
- `invalid-rule-code` (RUF102)
- `invalid-suppression-comment` (RUF103)
- `unmatched-suppression-comment` (RUF104)
- `replace-str-enum` (UP042)

The following behaviors have been stabilized:

- The `--output-format` flag is now respected when running Ruff in `--watch` mode, and the `full` output format is now used by default, matching the regular CLI output.
- `builtin-attribute-shadowing` (A003) now detects the use of shadowed built-in names in additional contexts like decorators, default arguments, and other attribute definitions.
- `duplicate-union-member` (PYI016) now considers `typing.Optional` when searching for duplicate union members.
- `split-static-string` (SIM905) now offers an autofix when the `maxsplit` argument is provided, even without a `sep` argument.
- `dict-get-with-none-default` (SIM910) now applies to more types of key expressions.
- `super-call-with-parameters` (UP008) now has a safe fix when it will not delete comments.
- `unnecessary-default-type-args` (UP043) now applies to stub (`.pyi`) files on Python versions before 3.13.

Formatter
This release introduces the new 2026 style guide, with the following changes:

- Lambda parameters are now kept on the same line and lambda bodies will be parenthesized to let them break across multiple lines (#21385)
- Parentheses around tuples of exceptions in `except` clauses will now be removed on Python 3.14 and later (#20768)
- A single empty line is now permitted at the beginning of function bodies (#21110)
- Parentheses are avoided for long `as` captures in `match` statements (#21176)
- Extra spaces between escaped quotes and ending triple quotes can now be omitted (#17216)
- Blank lines are now enforced before classes with decorators in stub files (#18888)

Preview features
- Apply formatting to Markdown code blocks (#22470, #22990, #22996)

See the documentation for more details.

Bug fixes
- Fix suppression indentation matching (#22903)

Rule changes
- Customize where the `fix_title` sub-diagnostic appears (#23044)
- [FastAPI] Add sub-diagnostic explaining why a fix was unavailable (FAST002) (#22565)
- [flake8-annotations] Don't suggest `NoReturn` for functions raising `NotImplementedError` (ANN201, ANN202, ANN205, ANN206) (#21311)
- [pyupgrade] Make fix unsafe if it deletes comments (UP017) (#22873)
- [pyupgrade] Make fix unsafe if it deletes comments (UP020) (#22872)
- [pyupgrade] Make fix unsafe if it deletes comments (UP033) (#22871)
- [refurb] Do not add `abc.ABC` if already present (FURB180) (#22234)
- [refurb] Make fix unsafe if it deletes comments (FURB110) (#22768)
- [ruff] Add sub-diagnostics with permissions (RUF064) (#22972)

Server
- Identify notebooks by LSP `didOpen` instead of `.ipynb` file extension (#22810)

CLI
- Add `--color` CLI option to force colored output (#22806)

Documentation
- Document `-` stdin convention in CLI help text (#22817)
- [refurb] Change example to `re.search` with `^` anchor (FURB167) (#22984)
- Fix link to Sphinx code block directives (#23041)
- [pydocstyle] Clarify which quote styles are allowed (D300) (#22825)
- [flake8-bugbear] Improve docs for `no-explicit-stacklevel` (B028) (#22538)

Other changes
- Update MSRV to 1.91 (#22874)