There's a lot of conflicting information online about using Haskell, Nix, Stack, Cabal, and Spacemacs together. Here's what has worked and not worked for me.
default.nix
:
{ pkgs ? import <nixpkgs> {} }: pkgs.haskellPackages.callCabal2nix "name" ./. { }
shell.nix
:
with import <nixpkgs> { };