This wasn't a hypothetical. I'm still not sure I made the right choice.

I decided to go with GHC via nix-shell, which worked fine, but it's a different path than I went with installing Rust (global rustup), and I'm not sure how to evaluate the pros/cons of each. I miss having ghci invocable anywhere, but doubt that's a good reason to change.

Also, ghcup failing on my Rasberry Pi was a fun troubleshooting experience! I don't remember how I got around that one either, but they eventually fixed the issue.