I don't see how your suggestion helps in the "I changed standard library and there are 10000 downstream test to rerun" use case, which is what they blogged abou

I don't see how your suggestion helps in the "I changed standard library and there are 10000 downstream test to rerun" use case, which is what they blogged about. You either: * Just don't test such changes at change time, break down and push the testing effort to downstream projects in disguise of "dependency management". * Structure your engineering effort to avoid such changes, for example avoid having a base library shared between teams. Neither is ideal for a corporation environment, because both harms velocity. We accept these in the "open source world" because we don't have better options, but the same does not hold for corps.