> I don't quite know why they made the choice they made. It was mostly technical one. Piper itself is a distributed file system which has significant incompati

> I don't quite know why they made the choice they made. It was mostly technical one. Piper itself is a distributed file system which has significant incompatibility with git's internal model and git didn't provide a good extension model to hack with. So to provide deep integration, forking was the only viable option at the moment. Perhaps the equation might be different now since MS did some contribution for their own use and git maintainers have become less reluctant to accept features for monorepo use cases, IIRC. Still, it's harder to retrofit the existing distributed file system into the core git object model than to develop a new one designed with that in mind.