anchor.diff:  {lib, stdenv, fetchFromGitHub
  +, buildPackages
   , curl, makeWrapper, which, unzip
   , lua
   # for 'luarocks pack'
  
positive.code:     fi
    '';
  
    nativeBuildInputs = [ makeWrapper installShellFiles ];
  
    buildInputs = [ lua curl which ];
  
  
negative.code:     installShellCompletion --cmd luarocks --zsh <($out/bin/luarocks completion zsh)
    '';
  
    propagatedNativeBuildInputs = [ zip unzip cmake ];
  
    # unpack hook for src.rock and rockspec files
    setupHook = ./setup-hook.sh;
  