shell.nix

let
  myHaskellPackageOverlay = self: super: {
    myHaskellPackages = super.haskellPackages.override {
    overrides = hself: hsuper: {
        mkDerivation = args: hsuper.mkDerivation (args // {
          doCheck = false;
          doHaddock = false;
          jailbreak = true;
        });
        random = hself.callCabal2nix "random" (builtins.fetchGit {
                url = "https://github.com/idontgetoutmuch/random.git";
                rev = "023e812545d2fac849ae64058d64590a63d2fe89";
                ref = "avoid-name-clash";
              }) { };
      };
    };
  };

  nixpkgs = import <nixpkgs> { overlays = [ myHaskellPackageOverlay ]; };
in

let

  haskellDeps = ps: with ps; [
  ps.pcg-random
  ps.random
  ps.QuickCheck
  ps.splitmix
  ];

in

  nixpkgs.stdenv.mkDerivation {
    name = "env";
    buildInputs = [
      (nixpkgs.myHaskellPackages.ghcWithPackages haskellDeps)
    ];
  }