Audience
Developers seeking to run fast unit tests with Vite-native tooling, Jest-compatible APIs, and integrated modern web development workflows
About Vitest
Vitest is a next-generation testing framework powered by Vite, designed to make testing fast, lightweight, and closely integrated with modern JavaScript development. Because it builds on Vite, Vitest understands existing Vite configuration and can reuse the same resolve and transform pipelines used by an application during development and builds. It can also be used without Vite and works for backend code as well. Vitest provides a Jest-compatible API, including expect assertions, snapshots, mocking, and coverage, making migration from Jest straightforward for many projects. Its smart watch mode reruns only tests related to changed files, using an experience similar to Vite’s instant Hot Module Replacement. Vitest supports ESM, TypeScript, and JSX out of the box, reducing the need for separate transformation configuration.