so Go has the same issues in my experience. but instead of "solver failed" you get compilation errors. I definitely had to fork a nontrivial amount of Go libraries to maintain my startup's backend.

"solver failed" is in theory a better error. it fails faster and is unambiguous. maybe because it's weird it is scarier? idk

the main issue is managing PVP bounds is a little hard to keep correct. but cabal also lets you "allow-newer" for duct tape.