Vitest 2.0 vs Jest: We migrated a 400-test Jest suite last month. Runtime dropped from 47 seconds to 11 seconds. Here is the honest breakdown. Why Vitest 2.0 Is Worth the Switch Vitest 1.x was already faster than Jest for TypeScript projects because it reuses Vite's transform pipeline instead of running ts-jest or babel-jest. Vitest 2.0 adds: Browser mode — run tests in Chromium/Firefox/WebKit