That might be true, but at least when I was at Google, people were not building and releasing their software to pick up HEAD of libraries they depended on. Som

That might be true, but at least when I was at Google, people were not building and releasing their software to pick up HEAD of libraries they depended on. Some binaries running in production could be quite old and seemed to communicate with newer builds just fine. (I suppose if there was a problem someone would have built a new version, though.)