> Although seemingly innocuous, this made maintaining internal libraries very challenging. There was no way to update every call site of your library in an effi

> Although seemingly innocuous, this made maintaining internal libraries very challenging. There was no way to update every call site of your library in an efficient way. Tools like Rosie were added on top so that you could shard your PRs and shepherd many PRs through a Byzantine approval process. Ownership is the easiest issue to solve here. Beyond a few dozen clients, you're going to run into the inability to run tests fast enough, and beyond a few hundred clients, you won't be able to sync fast enough, even if you skip all presubmits (there will, in expectation, always be a merge conflict in some file). 3-stage migrations/rosie are necessary at that point anyway. Owners is only the problem at like, 5-10 clients, and when I made changes at that scale, messaging owners was usually fast and effective.