anchor.diff:  { stdenv
  -, fetchurl
  +, fetchzip
   , makeWrapper
   , perl
   , pkgconfig
   , python
  +, waf
   , which
   
   , alsa-lib
  
positive.code:     xorg.libXxf86vm
    ];
  
    postPatch = ''
      patchShebangs ./TOOLS/
    '';
  
    configureFlags = [
      "--enable-libmpv-shared"
      "--disable-libmpv-static"
  
negative.code:     perl
      python
      pythonPackages.docutils
      waf
      which
    ];
  
  