Best Open-source Code Quality & Review Automation tools

Checkstyle

Enforce Java coding standards automatically across your codebase

reviewdog

Automated lint feedback directly in pull‑request reviews.

Kodus

AI-powered code reviews that learn your team's standards

Mutant

Automated Ruby code reviews that simplify code and ensure test safety

PR-Agent

AI-driven code reviews you can host and customize yourself

SonarQube

Continuous code inspection platform with quality gates and clean code enforcement

Shippie

AI-powered code reviewer that speeds up CI/CD pipelines

Danger

Automate pull‑request checks and enforce team code‑review standards.

Sourcery

Instant AI-powered code reviews for faster, higher-quality development

Hound

Automated style guide enforcement for GitHub pull requests.