[seddona]

Maybe try contributing to a large Haskell codebase first to get a feel for what Haskell is like in in-the-large and gain some comfort.

I'll add this problem is not at all Haskell specific. If you put an experienced Java developer to work architecting a large Python application where they have no prior Python experience you are going to experience similar problems. I'd say the problem is perhaps a bit more acute with Haskell as the paradigm is likely more different to the prior language. So if possible get at least one person on your team that has experience with a large Haskell app and pair them up with other devs.