Testing

The Workers platform has a variety of ways to test your applications, depending on your requirements. We recommend using the Vitest integration, which allows you to run tests inside the Workers runtime, and unit test individual functions within your Worker.

Get started with Vitest

Testing comparison matrix

However, if you don't use Vitest, both Miniflare's API and the unstable_startWorker() API provide options for testing your Worker in any testing framework.

Feature	Vitest integration	`unstable_startWorker()`	Miniflare's API
Unit testing	✅	❌	❌
Integration testing	✅	✅	✅
Loading Wrangler configuration files	✅	✅	❌
Use bindings directly in tests	✅	❌	✅
Isolated per-test storage	✅	❌	❌
Outbound request mocking	✅	❌	✅
Multiple Worker support	✅	✅	✅
Direct access to Durable Objects	✅	❌	❌
Run Durable Object alarms immediately	✅	❌	❌
List Durable Objects	✅	❌	❌
Test Durable Object eviction	✅	❌	❌
Testing service Workers	❌	✅	✅