Running Tests

jiki can run JavaScript test suites directly in the browser using Jest or Vitest. Test results come back in real time without sending code to a server — useful for coding tutorials, interview platforms, or any scenario where you want client-side test execution.

Both runners rely on jiki’s kernel for module resolution and transpilation. Test files are discovered on the virtual filesystem, transpiled as needed, and executed inside the container. The output can be displayed in a custom UI or streamed to a terminal component.

Choosing a test runner

Vitest tends to be a better fit for jiki because it shares Vite’s module transformation pipeline — startup is faster and the dependency footprint is smaller. Jest works too but needs more configuration for TypeScript and ESM. Both runners use the describe/it/expect API, so the choice often comes down to what your project already uses.