Ruff vs DeepSource

Free and open source

From $8 per user/month (indicative, Starter)

Free and open source. You pay in engineering time and CI minutes.

Among the cheapest per-developer options with autofix included.

Everything, self-hosted

Free for open source and small teams.

Category standard

Astral · since 2022

Established

DeepSource · since 2019

• Replaces Flake8, isort, Black, pyupgrade and more with a single fast binary.
• Fast enough to run on every keystroke in the editor.
• Straightforward migration from existing Flake8 configurations.

• Autofix commits remove the tedious half of acting on findings.
• Low false-positive rate keeps developers engaged with the tool.
• Cheap and quick to adopt.

• Not every niche Flake8 plugin rule has been ported.
• Type checking is a separate concern — you still need mypy or ty.
• Rapid release cadence occasionally changes behaviour.

• Narrower language coverage than SonarQube.
• Smaller vendor with less enterprise governance tooling.
• Autofix still needs review — it is not unattended.

Every Python project.

Teams that want static analysis developers do not resent.