Japa Lean Node.js Test Runner

Japa is a lean and fast Node.js test runner designed for both testing applications and for building custom test runners. The current stable version is v10.4.0, with minor and patch releases occurring frequently—typically several times a quarter—and major versions released periodically as breaking changes are introduced. A key differentiator is its minimal core, offering faster boot times compared to alternatives like Mocha or Ava, primarily because it does not ship with its own CLI; tests are executed directly as standard Node.js scripts. Japa supports ES6 async/await syntax, ES modules, test groups with lifecycle hooks, regression tests, and offers an extensible assertion system often utilized via plugins. Its design philosophy emphasizes simplicity and provides the foundational components for highly customized testing environments.