default.nix

let
  pkgs = import <nixpkgs> {};
  compilerVersion = "ghc865"; 
  compiler = pkgs.haskell.packages."${compilerVersion}";
in
compiler.developPackage
  {
    # returnShellEnv = false;
    
    root = ./.;
    
    # source-overrides = {};
    
    modifier = drv:
      let pkg = pkgs.haskell.lib.addBuildTools drv (with pkgs.haskellPackages;
        [
          cabal-install
          cabal2nix
          ghcid
        ]);
      in pkg // {
        env = (pkg.env { withHoogle = true; }).overrideAttrs (old: {
          shellHook =
            ''
              export PS1='\n\[\033[1;32m\][\[\e]0;nix-shell: \W\a\]nix-shell:/\W]\$ \[\033[0m\]'
            '';
        });
      };
  }