Ruff

Ruff is a Python linter and code formatter written in Rust, designed to be much faster than existing tools such as Flake8 and Black. It is installable with pip and configured through pyproject.toml.

Ruff offers drop-in parity with Flake8, isort and Black, more than 900 built-in rules including native re-implementations of popular Flake8 plugins such as flake8-bugbear, automatic fixes (for example removing unused imports), built-in caching of unchanged files, editor integrations including VS Code, and hierarchical configuration suited to monorepos.

Ruff is developed by Astral, distributed under the MIT licence and actively maintained on GitHub; version 0.17.1 was released in October 2026.