Jest is a comprehensive JavaScript testing solution that works out of the box for most JavaScript projects. It provides fast interactive watch mode (running related tests for changed files) and supports snapshot testing to track how large objects change over time.
Project status
- Jest (jestjs/jest) appears actively maintained, with recent upstream activity as of 2026-06-02 and multiple tagged
v30.4.xupdates in early May 2026. - The apparent update cadence is tight around the
v30.4line (v30.4.0 on 2026-05-07, followed by v30.4.1 on 2026-05-08, and v30.4.2 on 2026-05-09), suggesting rapid follow-up after a major change.
AI summary generated Today
Recent updates
v30.4.2
3 weeks agoJest v30.4.2 focuses on fixing ESM/CJS interop in jest-runtime, specifically named imports when a CJS module sets `module.exports` to a function that also has own-property exports. The code change expands how `buildCjsAsEsmSyntheticModule` interprets `module.exports`, and adds end-to-end and unit coverage for this interop scenario.
v30.4.1
3 weeks agov30.4.1 adds support for configuring custom test runners with runner options via a tuple form, and ensures runner options are propagated into the runner at construction time. It also aligns Jest's CJS-from-ESM default export behavior with Node's behavior by adjusting __esModule unwrapping.
BreakingFeaturesv30.4.0
3 weeks agov30.4.0 is a major Jest release focused on a rewrite of the custom runtime to better support native ESM behaviors and upcoming stabilization work. It adds Node 24.9+ support for require() of ESM (still requiring --experimental-vm-modules), expands Temporal support in fake timers, and improves React 19 snapshot formatting. The release also introduces several CLI/config enhancements (for collecting test names without running them, graceful worker exits, and jest.config.mts).
Features