Overview

Changesets is a tool for managing versioning and changelogs with a focus on multi-package repositories (monorepos). Created and battle-tested by the Atlassian team, Changesets provides a structured workflow where contributors declare how their changes should be released, and the tool automates version bumps, changelog updates, and package publishing.

The core concept is the “changeset” — a markdown file that describes an intent to release one or more packages at specific semver bump levels (major, minor, or patch) along with a human-readable summary. Multiple changesets accumulate over time and are combined into a single release that correctly handles internal dependency relationships between packages in a monorepo.

How It Works

The @changesets/cli package provides the command-line interface. When a developer makes a change, they run npx changeset which prompts them to select affected packages, choose bump types, and write a summary. This creates a markdown file in a .changeset directory that gets committed with the code change.

At release time, running npx changeset version consumes all pending changeset files, calculates the final version bump for each package (flattening multiple changesets into a single bump), updates package.json versions, adjusts internal dependency references, and generates changelog entries. Then npx changeset publish publishes all updated packages to npm.

Automation and Integration

Changesets provides a GitHub bot that checks PRs for changeset files and a GitHub Action that automates the entire release flow by creating versioning pull requests and optionally publishing packages. The project is used by Atlaskit, Emotion, Keystone, XState, pnpm, React Select, and many other major open source projects. With over 11,000 GitHub stars and a rich ecosystem of plugins for custom changelog formats, Changesets is the standard tool for monorepo release management in the JavaScript ecosystem.