x/build/cmd/coordinator: use cmd/go's build caching #28950
Would both the trybots and builders use caching? I presume that trybots are the ones where total run-time matters the most.
I agree that this would be a good step forward. One possible disadvantage I can see is that we would test the compiler less often. It's easier to catch flakes and very unlikely crashes in the compiler if every builder compiles the entirety of Go at every run. I wonder if it would be a problem if we lost that, though.