
Originally Posted by
frantaylor
At a big development house, when an incompatible change is pushed to the release branch, the testing department descends on the build like an unholy swarm. Hundreds of thousands of unit tests are run overnight by large teams of testers and entire buildings filled with servers. Every single customer regression that has ever been reported has been encoded as an automatic test. Companies that "eat their own dog food" will transition their own internal systems over to the new build before ship. They put the daily operation of their company on the line when they do this so it requires great confidence and a solid arrogant intolerance for problems.