reviewdog is a language-agnostic automated code review tool that acts as a universal adapter between any linter or static analysis tool and code hosting platforms. Created by Japanese developer haya14busa, it parses diagnostic output from tools in multiple formats including Vim-style errorformat, Checkstyle XML, SARIF, JSON Lines, and unified diff. The parsed results are posted as inline review comments directly on pull request diffs, ensuring developers see issues exactly where they occur in the changed code.
The tool integrates with all major CI platforms including GitHub Actions, GitLab CI, CircleCI, Travis CI, Bitbucket Pipelines, and Jenkins. A key differentiator is its diff-aware filtering — reviewdog only reports issues on newly changed lines, preventing existing technical debt from flooding pull request reviews. Dedicated GitHub Actions exist for popular linters like eslint, golangci-lint, shellcheck, rubocop, and actionlint, while the generic interface supports any tool that outputs diagnostic messages.
With 9,200 GitHub stars and MIT licensing, reviewdog has become essential infrastructure for development teams that want consistent automated code quality checks across their entire stack. A single reviewdog.yml configuration file defines which linters run against which file patterns, working identically in CI and local development. The tool supports code suggestion comments on supported platforms, allowing reviewers to accept automated fixes with one click directly from the pull request interface.
