ruff

Ruff Docs | Playground An extremely fast Python linter and code formatter, written in Rust. Linting the CPython codebase from scratch. ⚡️ 10-100x faster than existing linters (like Flake8) and formatters (like Black) 🐍 Installable via pip 🛠️ pyproject.toml support 🤝 Python 3.15 compatibility ⚖️ Drop-in parity with Flake8, isort, and Black 📦 Built-in caching, to avoid re-analyzing unchanged files 🔧 Fix support, for automatic error correction (e.g., automatically remove unused imports) 📏 Over 900 built-in rules, with native re-implementations of popular Flake8 plugins, like flake8-bugbear ⌨️ First-party editor integrations for VS Code and more 🌎 Monorepo-friendly, with hierarchical and cascading configuration Ruff aims to be orders of magnitude faster than alternative tools while integrating more functionality behind a single, common interface. Ruff can be used to replace Flake8 (plus dozens of plugins), Black, isort, pydocstyle, pyupgrade, autoflake, and more, all while executing tens or hundreds of times faster than any individual tool. Ruff is actively developed and used in major open-source projects like: Apache Airflow Apache Superset FastAPI Hugging Face Pandas SciPy Ruff is backed by Astral, the creators of uv and ty. Read the launch post, or the original project announcement. Testimonials Sebastián Ramírez, creator of FastAPI: Ruff is so fast that sometimes I add an intentional bug in the code just to confirm it's actually running and checking the code. Nick Schrock, founder of Elementl, co-creator of GraphQL: Why is Ruff a gamechanger? Primarily because it is nearly 1000x faster. Literally. Not a typo. On our largest module (dagster itself, 250k LOC) pylint takes about 2.5 minutes, parallelized across 4 cores on my M1. Running ruff against our entire codebase takes .4 seconds. Bryan Van de Ven, co-creator of Bokeh, original author of Conda: Ruff is ~150-200x faster than flake8 on my machine, scanning the whole repo takes ~0.2s instead of ~20s. This is an enormous quality of life improvement for local dev. It's fast enough that I added it as an actual commit hook, which is terrific. Timothy Crosley, creator of isort: Just switched my first project to Ruff. Only one downside so far: it's so fast I couldn't believe it was working till I intentionally introduced some errors. Tim Abbott, lead developer of Zulip (also here): This is just ridiculously fast... ruff is amazing. Table of Contents For more, see the documentation. Getting Started Configuration Rules Contributing Support Acknowledgements Show Your Support License Getting Started For more, see the documentation. Installation Ruff is available as ruff on PyPI. Invoke Ruff directly with uvx: uvx ruff@0.17.3 check # Lint all files in the current directory. uvx ruff@0.17.3 format # Format all files in the current directory. Or install Ruff with uv (recommended), pip, or pipx: # With uv. uv tool install ruff@latest # Install Ruff globally. uv add --dev ruff # Or add Ruff to your project. # With pip. pip install ruff # With pipx. pipx install ruff Starting with version 0.5.0, Ruff can be installed with our standalone installers: # On macOS and Linux. curl -LsSf https://astral.sh/ruff/install.sh | sh # On Windows. powershell -c "irm https://astral.sh/ruff/install.ps1 | iex" # For a specific version. curl -LsSf https://astral.sh/ruff/0.17.3/install.sh | sh powershell -c "irm https://astral.sh/ruff/0.17.3/install.ps1 | iex" You can also install Ruff via Homebrew, Conda, and with a variety of other package managers. Usage To run Ruff as a linter, try any of the following: ruff check # Lint all files in the current directory (and any subdirectories). ruff check path/to/code/ # Lint all files in `/path/to/code` (and any subdirectories). ruff check path/to/code/*.py # Lint all `.py` files in `/path/to/code`. ruff check path/to/code/to/file.py # Lint `file.py`. ruff check @arguments.txt # Lint using an input file, treating its contents as newline-delimited command-line arguments. Or, to run Ruff as a formatter: ruff format # Format all files in the current directory (and any subdirectories). ruff format path/to/code/ # Format all files in `/path/to/code` (and any subdirectories). ruff format path/to/code/*.py # Format all `.py` files in `/path/to/code`. ruff format path/to/code/to/file.py # Format `file.py`. ruff format @arguments.txt # Format using an input file, treating its contents as newline-delimited command-line arguments. Ruff can also be used as a pre-commit hook via ruff-pre-commit: - repo: https://github.com/astral-sh/ruff-pre-commit # Ruff version. rev: v0.17.3 hooks: # Run the linter. - id: ruff-check args: [ --fix ] # Run the formatter. - id: ruff-format Ruff can also be used as a VS Code extension or with various other editors. Ruff can also be used as a GitHub Action via ruff-action: name: Ruff on: [ push, pull_request ] jobs: ruff: runs-on: ubuntu-latest steps: - uses: actions/checkout@v4 - uses: astral-sh/ruff-action@v3 Configuration Ruff can be configured through a pyproject.toml, ruff.toml, or .ruff.toml file (see: Configuration, or Settings for a complete list of all configuration options). For the complete list of enabled rules, see Default Rules. If left unspecified, Ruff's default configuration is equivalent to the following ruff.toml file: # Exclude a variety of commonly ignored directories. exclude = [ ".bzr", ".direnv", ".eggs", ".git", ".git-rewrite", ".hg", ".ipynb_checkpoints", ".mypy_cache", ".nox", ".pants.d", ".pyenv", ".pytest_cache", ".pytype", ".ruff_cache", ".svn", ".tox", ".venv", ".vscode", "__pypackages__", "_build", "buck-out", "build", "dist", "node_modules", "site-packages",