Vitest
Vite-native unit and component test runner with a Jest-compatible API.
UnitComponent
At a glance
Parallelismhigh
Learning curvelow
CI fithigh
LanguagesTypeScript, JavaScript
Runner: Vite-powered runner with native ESM and instant HMR-style watch.
Strengths
- Very fast; reuses the Vite pipeline so config is shared with the app.
- Jest-compatible API eases migration; first-class ESM and TypeScript.
- Built-in coverage, watch, and UI.
Trade-offs
- Best inside a Vite-centric stack; outside it the benefits shrink.
- Younger than Jest, though it has matured quickly.
When to use
Reach for Vitest for unit and component tests in any Vite or modern-ESM project that wants speed and shared config — this site uses it.