Ruff

astral-sh/ruffReviewed by AI

What it does

Ruff is a terminal tool for people who write Python. It scans a project's Python files, points out over 900 kinds of problems such as unused imports, can fix many of them automatically, and reformats the code in a style close to Black's. It is written in Rust and ships as a ready binary for Windows, macOS and Linux (about 10 MB), installable with pip, uv, Homebrew or the project's own install script. It also plugs into VS Code and other editors.

How easy it is to install

C · install 1 or 2 tools · Windows

Windows C
macOS C
Linux C

Equal on the three platforms: ready binaries are published for each one, but Ruff has no window or buttons, so you install it with a command (pip, uv, Homebrew or the install script) and then type commands such as `ruff check` in a terminal.

Numbers on GitHub

Stars: 50,369on Oct 31, 2026
Downloads: 38,310,266853,755 this week
Growth: +52stars in 5 days

Stars over time

Facts

Runs on: Windows, macOS, Linux
You need to install: Python
To build from source: Python, Docker, Rust
Disk space: 10 MB–29 MB · from the installer
Accounts or keys: None
Cost: Free · MIT license; the company behind it, Astral, sells other products.
License: MIT (Permissive)
Last update: Oct 31, 2026

Risk signals (1)

Infoinstall script piped from web
README.md installation section suggests `curl -LsSf https://astral.sh/ruff/install.sh | sh` on macOS and Linux and `powershell -c "irm https://astral.sh/ruff/install.ps1 | iex"` on Windows, which runs a script downloaded from astral.sh without showing it first.
AI review

Evidence is shown in its original language.

What Radar could not check

Whether the published binaries match the source code in this repository
How many of the fixes it applies automatically are the ones you actually want
Whether the checks behave the same on your Python version and project layout