Gerrit

Gerrit Code Review is a web-based code review tool for Git. It provides a review-centric workflow that sits between developers’ local Git repositories and the central codebase, emphasizing discussion, inline comments, and controlled integration. Gerrit stores each change as a set of patch sets and aggregates review comments, approvals, and verification results in a single record associated with the change.

Core concepts in Gerrit include changes, patch sets, and labels. Developers push reviews to special refs (for example refs/for/*) to create new patch sets. Reviewers can leave inline comments and apply scores using Code-Review and Verified labels. A change can be submitted only when project-defined submission rules are satisfied and any required CI checks have passed. Gerrit integrates with continuous integration systems and notification channels and provides a REST API and a plugin framework for customization.

Architecturally, Gerrit runs as a server with a web user interface and stores data in a database-backed backend. It is open-source software released under the Apache License 2.0 and is used by many organizations and open-source projects. Gerrit is particularly valued for large-scale code bases and for workflows that require formal, auditable review before changes are merged. The Android Open Source Project is a notable example of a Gerrit-based development workflow.