I’ve been using Nix to develop and deploy Haskell for quite some time now and I’d like to share some of the gems I have found/figured out here. For this post I want to focus on just project development. I’m no expert and I’m sure community members will have additions/improvements on what I post. Hopefully we can distill this post into a new wiki entry afterwards.  Pinning Nixpkgs There are two easy ways to pick a specific commit of sources, niv or nix-prefetch-git (install with nix-env -i nix-pr...