Why you can't ship reliable APIs without end-to-end tests

Mon, 02 Nov 2026 00:00:00 +0000

Unit tests prove your code does what you thought. Contract tests prove the shape of your interface. Only end-to-end tests prove the system keeps its promise to the people who depend on it, and they don't have to be slow or flaky.

QualityEngineering on Bufon

Why you can't ship reliable APIs without end-to-end tests