anchor.diff:      cp -r {cmd,vlib,thirdparty} $out/lib
       mv v $out/lib
       ln -s $out/lib/v $out/bin/v
  +    wrapProgram $out/bin/v --prefix PATH : ${lib.makeBinPath [ stdenv.cc ]}
       runHook postInstall
     '';
   
  
positive.code: { lib, stdenv, fetchFromGitHub, glfw, freetype, openssl, upx ? null }:
  
  assert stdenv.hostPlatform.isUnix -> upx != null;
  
  stdenv.mkDerivation rec {
    pname = "vlang";
  
negative.code:   propagatedBuildInputs = [ glfw freetype openssl ]
      ++ lib.optional stdenv.hostPlatform.isUnix upx;
  
    nativeBuildInputs = [ makeWrapper ];
  
    makeFlags = [
      "local=1"
      "VC=${vc}"
      # vlang seems to want to write to $HOME/.vmodules , so lets give
      # it a writable HOME
      "HOME=$TMPDIR"
    ];
  
    installPhase = ''
      runHook preInstall
  