> Well now you have to tell us why and how 600 people are sharing a repo
Any answer you could possibly get from this question will eventually boil down to project repos vs monorepo. There are pros and cons to each, which are more or less meaningless depending on the amount of developers working in parallel.
I figured as much, and just wondered about the challenges of trunk based development with a large contributor pool. If so many teams are working in different subtrees of the monorepo, it seems like trunk based development could be just fine.
