nix-shell with custom Haskell packages

default.nix

with import <nixpkgs> { };

let
  proto3-wire-src = fetchFromGitHub {
    owner = "awakenetworks";
    repo = "proto3-wire";
    rev = "4f355bbac895d577d8a28f567ab4380f042ccc24";
    sha256 = "16l1rnnygwk1b2sb3l6klhr6ad0wvry204icxnc81c6rbzbk6rqc";
  };

  proto3-suite-src = fetchFromGitHub {
    owner = "awakenetworks";
    repo = "proto3-suite";
    rev = "3f6dd6f612cf2eba3c05798926ff924b0d5ab4fa";
    sha256 = "0g7j7axx9rkrzw32ky9xl08zj34rx4mqafd89lrpnsi8lcq2z06j";
  };

  hs = haskellPackages.override {
    overrides = self: super: rec {
      proto3-wire = haskell.lib.dontCheck
        (self.callCabal2nix "proto3-wire" proto3-wire-src { });
      proto3-suite = haskell.lib.dontCheck
        (self.callCabal2nix "proto3-suite" proto3-suite-src { });
    };
  };

in
  runCommand "dummy" {
    buildInputs = [ (hs.ghcWithPackages (p: [p.proto3-suite])) ];
    GHC_ENVIRONMENT = "-";
  } ""