If you have the same functionality that can't be re-used (for no reason), then I'd call that a design flaw. I'll need a few more validation functions for each

If you have the same functionality that can't be re-used (for no reason), then I'd call that a design flaw. I'll need a few more validation functions for each clients. I don't want to write+maintain multiple functions that do the same thing, even if it's just copy+paste. It's "data" validation. So let's put that in the "data layer" repo. We now have, at least: - Server - Web (GUI) - Android - iOS - Data - More clients? We'll also have branches for each development task. How do we know what branch the other branches should use? One "simple" feature can easily spread over multiple repos. Does each repo refer to the repo+branch it depends upon (don't forget to update the references when we merge!), or we add a "build" repo which acts as the orchestrator? Most PRs will need to be daisy chained - who reviews each one? Will they get comitted at the same time? How do we make the builds reproducible? commit hashes? tags? ok, we now need to tag each repo, and update the references to point to that tag/hash... but that changes the build. Well, I'm glad our code base is split over multiple repos because "scalability".