Of course, you have to test your code. But testing is not a good way to demonstrate absence of unknown bugs and incompatibilities. You don’t know that an unkno

Of course, you have to test your code. But testing is not a good way to demonstrate absence of unknown bugs and incompatibilities. You don’t know that an unknown issue exist until you have a test that exercises that particular code path which triggers an issue. Semver looks like a promise “upgrade from 1.5.0 to 1.17.5 is always compatible” but this promise can still be broken, with probability dependent on the depth and breadth of your dependency tree. It’s frustrating to see this promise broken when you find an issue, write a test, downgrade the dependency to semver-compatible version, and the test passes.