Vitest is a next-generation testing framework powered by Vite. It provides a Jest-compatible API with native ESM, TypeScript, and JSX support out of the box. Vitest shares the same config, transformers, resolvers, and plugins with your Vite app. Key Features: - Vite-native: Uses Vite's transformation pipeline for fast HMR-like test updates - Jest-compatible: Drop-in replacement for most Jest test suites - Smart watch mode: Only reruns affected tests based on module graph - Native ESM, TypeScript, JSX support without configuration - Multi-threaded workers for parallel test execution - Built-in…