Beyond End-to-End: Why Your Microservices Need Contract Testing
You push a small code update. Your unit tests are green, and the functional tests pass. You feel confident. The release pipeline triggers, and the new feature hits production. Ten minutes later, your monitoring dashboard lights up with errors. The frontend team updated a User ID field from an integer to a string, and your backend service just choked on it. In a monolithic design, the compiler or a rudimentary integration suite often identifies these issues.