@rzeta0 It's okay to skip the stack/cabal/etc if the code has no dependencies besides `base`.
Otherwise, switch to the project-based setup ASAP and save hours trying to figure out how to install stuff, where, and which versions.
Since the package they use for exercises has quite a few deps, you'd rather follow the suit and `ghcup install stack` or make yourself at least a minimal `cabal.project` (`packages: .`) and use `cabal ghci ...` instead.
Just don't try to `cabal install` - this way lies madness.
Apparently they use stack to install ghc too. That was superceded by ghcup.