anchor.diff:  
     preFixup = /* Ensure youtube-dl is available in $PATH for MPV */ ''
       wrapProgram $out/bin/mpv \
  -      --prefix PATH : "${pythonPackages.youtube-dl}/bin"
  +      --prefix PATH : "${python3Packages.youtube-dl}/bin"
     '';
   
     meta = with lib; {
  
positive.code:   nativeBuildInputs = [
      makeWrapper
      perl
      pythonPackages.python
      pythonPackages.docutils
      waf
      which
    ];
  
negative.code:     openal
      opengl-dummy
      pulseaudio_lib
      python3Packages.youtube-dl
      rubberband
      samba_client
      sdl
  