ruff

A Dagger module — written in the .dang module language — that wraps ruff, the extremely fast Python linter and formatter.

Ruff ships as a self-contained static binary, so this module extracts it from the pinned ghcr.io/astral-sh/ruff image (tracked by Dependabot via images/ruff/Dockerfile) and runs it on an Alpine base — no Python, pip, uv, or virtualenv required.

Functions

Function	Description
check	Lint with ruff check; fails on violations (a @check).
format-check	Verify formatting with ruff format --check; fails if unformatted.
lint	Return the lint report as text without failing on violations.
fix	Apply ruff check --fix and return the modified source directory.
format	Run ruff format and return the formatted source directory.
version	The version of the bundled ruff binary.

The constructor takes the project source from the workspace at sourcePath (default /). args are forwarded to every ruff invocation, and container overrides the default Alpine + ruff base.

Usage

Install the module in your workspace:

dagger install github.com/dagger/ruff

Check for lint and format issues:

dagger check

Or to only run the ruff module:

dagger check ruff

To apply the formatter:

dagger generate
dagger generate ruff