I totally get that sentiment about nix, and actually I sort of share a variation of it too: I really want to learn it, and I like the featureset in theory, but I can't get used to it in practice, and I don't have the time to invest myself into something that difficult to get going.

The reason I brought up the nix command is that I only use nix, for haskell development, for that specific command: I found it once in a blog post, saved it, then put it under a function into my bashrc, and I use nix quite literally for only that purpose. I've done a lot of development on various functional languages (with a dayjob in F# that lasted 3 years) and being able to quickly experiment with libraries was something that I sorely missed when doing repl experimentation in those languages (I think F# recently got a #nuget directive, but that was after I stopped using it).

Curious and interesting.

Not to be the party pooper: didn't Docker work well for your Haskell use-case?

I personally haven't had much chance to use docker with Haskell specifically, but I imagine that it would definitely work, it would just take a bit more work to get going, so I just take the option that is less friction (at least for my specific usecases). Nix is also somewhat popular in the haskell community - especially when it comes to GHCJS (with tools like obelisk making it easier to develop cross-platform apps using web tech). So I just go along with the flow of the community, personally, especially considering that I use Haskell exclusively for my own personal stuff (sadly).