Package: ruff
RuffDiscord|Docs|PlaygroundAn 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 viapip🛠️pyproject.tomlsupport🤝 Python 3.12 compatibility⚖️ Drop-in parity withFlake8, isort, and Black📦 Built-in caching, to avoid re-analyzing unchanged files🔧 Fix support, for automatic error correction (e.g., automatically remove unused imports)📏 Over700 built-in rules, with native re-implementations
of popular Flake8 plugins, like flake8-bugbear⌨️ First-partyeditor integrationsforVS Codeandmore🌎 Monorepo-friendly, withhierarchical and cascading configurationRuff aims to be orders of magnitude faster than alternative tools while integrating more
functionality behind a single, common interface.Ruff can be used to replaceFlake8(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 extremely actively developed and used in major open-source projects like:Apache AirflowFastAPIHugging FacePandasSciPy...andmany more.Ruff is backed byAstral. Read thelaunch post,
or the originalproject announcement.TestimonialsSebastián Ramírez, creator
ofFastAPI: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 ofElementl,
co-creator ofGraphQL: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 ourentirecodebase takes .4 seconds.Bryan Van de Ven, co-creator
ofBokeh, original author
ofConda: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 ofisort: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 ofZulip:This is just ridiculously fast...ruffis amazing.Table of ContentsFor more, see thedocumentation.Getting StartedConfigurationRulesContributingSupportAcknowledgementsWho's Using Ruff?LicenseGetting StartedFor more, see thedocumentation.InstallationRuff is available asruffon PyPI:pipinstallruffYou can also install Ruff viaHomebrew,Conda,
and witha variety of other package managers.UsageTo run Ruff as a linter, try any of the following:ruffcheck.# Lint all files in the current directory (and any subdirectories).ruffcheckpath/to/code/# Lint all files in `/path/to/code` (and any subdirectories).ruffcheckpath/to/code/*.py# Lint all `.py` files in `/path/to/code`.ruffcheckpath/to/code/to/file.py# Lint `file.py`.ruffcheck@arguments.txt# Lint using an input file, treating its contents as newline-delimited command-line arguments.Or, to run Ruff as a formatter:ruffformat.# Format all files in the current directory (and any subdirectories).ruffformatpath/to/code/# Format all files in `/path/to/code` (and any subdirectories).ruffformatpath/to/code/*.py# Format all `.py` files in `/path/to/code`.ruffformatpath/to/code/to/file.py# Format `file.py`.ruffformat@arguments.txt# Format using an input file, treating its contents as newline-delimited command-line arguments.Ruff can also be used as apre-commithook viaruff-pre-commit:-repo:https://github.com/astral-sh/ruff-pre-commit# Ruff version.rev:v0.2.2hooks:# Run the linter.-id:ruffargs:[--fix]# Run the formatter.-id:ruff-formatRuff can also be used as aVS Code extensionor
alongside any other editor through theRuff LSP.Ruff can also be used as aGitHub Actionviaruff-action:name:Ruffon:[push,pull_request]jobs:ruff:runs-on:ubuntu-lateststeps:-uses:actions/checkout@v3-uses:chartboost/ruff-action@v1ConfigurationRuff can be configured through apyproject.toml,ruff.toml, or.ruff.tomlfile (see:Configuration, orSettingsfor a complete list of all configuration options).If left unspecified, Ruff's default configuration is equivalent to:[tool.ruff]# 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","venv",]# Same as Black.line-length=88indent-width=4# Assume Python 3.8target-version="py38"[tool.ruff.lint]# Enable Pyflakes (`F`) and a subset of the pycodestyle (`E`)  codes by default.select=["E4","E7","E9","F"]ignore=[]# Allow fix for all enabled rules (when `--fix`) is provided.fixable=["ALL"]unfixable=[]# Allow unused variables when underscore-prefixed.dummy-variable-rgx="^(_+|(_+[a-zA-Z0-9_]*[a-zA-Z0-9]+?))$"[tool.ruff.format]# Like Black, use double quotes for strings.quote-style="double"# Like Black, indent with spaces, rather than tabs.indent-style="space"# Like Black, respect magic trailing commas.skip-magic-trailing-comma=false# Like Black, automatically detect the appropriate line ending.line-ending="auto"Some configuration options can be provided via the command-line, such as those related to
rule enablement and disablement, file discovery, and logging level:ruffcheckpath/to/code/--selectF401--selectF403--quietSeeruff helpfor more on Ruff's top-level commands, orruff help checkandruff help formatfor more on the linting and formatting commands, respectively.RulesRuff supports over 700 lint rules, many of which are inspired by popular tools like Flake8,
isort, pyupgrade, and others. Regardless of the rule's origin, Ruff re-implements every rule in
Rust as a first-party feature.By default, Ruff enables Flake8'sFrules, along with a subset of theErules, omitting any
stylistic rules that overlap with the use of a formatter, likeruff formatorBlack.If you're just getting started with Ruff,the default rule set is a great place to start: it
catches a wide variety of common errors (like unused imports) with zero configuration.Beyond the defaults, Ruff re-implements some of the most popular Flake8 plugins and related code
quality tools, including:autoflakeeradicateflake8-2020flake8-annotationsflake8-asyncflake8-bandit(#1646)flake8-blind-exceptflake8-boolean-trapflake8-bugbearflake8-builtinsflake8-commasflake8-comprehensionsflake8-copyrightflake8-datetimezflake8-debuggerflake8-djangoflake8-docstringsflake8-eradicateflake8-errmsgflake8-executableflake8-future-annotationsflake8-gettextflake8-implicit-str-concatflake8-import-conventionsflake8-loggingflake8-logging-formatflake8-no-pep420flake8-pieflake8-printflake8-pyiflake8-pytest-styleflake8-quotesflake8-raiseflake8-returnflake8-selfflake8-simplifyflake8-slotsflake8-superflake8-tidy-importsflake8-todosflake8-trioflake8-type-checkingflake8-use-pathlibflynt(#2102)isortmccabepandas-vetpep8-namingpydocstylepygrep-hookspylint-airflowpyupgradetryceratopsyesqaFor a complete enumeration of the supported rules, seeRules.ContributingContributions are welcome and highly appreciated. To get started, check out thecontributing guidelines.You can also join us onDiscord.SupportHaving trouble? Check out the existing issues onGitHub,
or feel free toopen a new one.You can also ask for help onDiscord.AcknowledgementsRuff's linter draws on both the APIs and implementation details of many other
tools in the Python ecosystem, especiallyFlake8,Pyflakes,pycodestyle,pydocstyle,pyupgrade, andisort.In some cases, Ruff includes a "direct" Rust port of the corresponding tool.
We're grateful to the maintainers of these tools for their work, and for all
the value they've provided to the Python community.Ruff's formatter is built on a fork of Rome'srome_formatter,
and again draws on both API and implementation details fromRome,Prettier, andBlack.Ruff's import resolver is based on the import resolution algorithm fromPyright.Ruff is also influenced by a number of tools outside the Python ecosystem, likeClippyandESLint.Ruff is the beneficiary of a large number ofcontributors.Ruff is released under the MIT license.Who's Using Ruff?Ruff is used by a number of major open-source projects and companies, including:Amazon (AWS SAM)Anthropic (Python SDK)Apache AirflowAstraZeneca (Magnus)BabelBenchling (Refac)BokehCryptography (PyCA)CERN (Indico)DVCDaggerDagsterDatabricks (MLflow)FastAPIGradioGreat ExpectationsHTTPXHatchHome AssistantHugging Face (Transformers,Datasets,Diffusers)ING Bank (popmon,probatus)IbisivyJupyterLangChainLitestarLlamaIndexMatrix (Synapse)MegaLinterMeltano (Meltano CLI,Singer SDK)Microsoft (Semantic Kernel,ONNX Runtime,LightGBM)Modern Treasury (Python SDK)Mozilla (Firefox)MypyNetflix (Dispatch)NeonNoneBotNumPyroONNXOpenBBPDMPaddlePaddlePandasPillowPoetryPolarsPostHogPrefect (Python SDK,Marvin)PyInstallerPyMCPyMC-MarketingpytestPyTorchPydanticPylintPyVistaReflexRiverRipplingRobynSaleorScale AI (Launch SDK)SciPySnowflake (SnowCLI)SphinxStable Baselines3StarletteThe AlgorithmsVega-AltairWordPress (Openverse)ZenMLZulipbuild (PyPA)cibuildwheel (PyPA)delta-rsfeaturetoolsmeson-pythonnoxpipShow Your SupportIf you're using Ruff, consider adding the Ruff badge to your project'sREADME.md:[![Ruff](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/astral-sh/ruff/main/assets/badge/v2.json)](https://github.com/astral-sh/ruff)...orREADME.rst:..image::https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/astral-sh/ruff/main/assets/badge/v2.json:target:https://github.com/astral-sh/ruff:alt:Ruff...or, as HTML:<ahref="https://github.com/astral-sh/ruff"><imgsrc="https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/astral-sh/ruff/main/assets/badge/v2.json"alt="Ruff"style="max-width:100%;"></a>LicenseMIT