Node.js Built-In Test Runner Now Rivals Jest and Vitest for Backend Projects

Node.js has included a built-in test runner since v18, which reached stable status in v20, but many developers continued defaulting to third-party frameworks out of habit. The runner now supports mocking, fake timers, watch mode, coverage output, and global setup hooks without requiring any additional dependencies. It also executes TypeScript files directly by stripping type annotations at runtime, though a separate type-checking step like tsc --noEmit is still needed in CI pipelines. Each test file runs in its own child process by default, providing file-level isolation out of the box. One key behavioral difference from Jest or Vitest is that subtests inside a bare test() block must be explicitly awaited, whereas using describe/it suites avoids this issue entirely.