$ cat default.nix
{ stdenv, bundlerEnv, ruby }:
let
env = bundlerEnv {
  name = "staytus";
  inherit ruby;
  gemfile  = ./Gemfile;
  lockfile = ./Gemfile.lock;
  gemset   = ./gemset.nix;
};
in stdenv.mkDerivation {
name = "staytus";
src = ./.;
buildInputs = [ ruby env ];
installPhase = ''
    mkdir -p $out
    cp -r $src $out
  '';
}