anchor.diff: -{ stdenv, fetchFromGitHub, ncurses, pkgconfig
  -, gcc, libiconv, CoreAudio
  +{ stdenv, fetchFromGitHub, runCommand, ncurses, pkgconfig
  +, libiconv, CoreAudio
   
   , alsaSupport ? stdenv.isLinux, alsaLib ? null
   # simple fallback for everyone else
  
positive.code:   ] ++ concatMap (a: a.flags) opts);
  
    buildInputs = [ ncurses pkgconfig ]
      ++ stdenv.lib.optional stdenv.cc.isClang gcc
      ++ stdenv.lib.optionals stdenv.isDarwin [ libiconv CoreAudio ]
      ++ concatMap (a: a.deps) opts;
  
  
negative.code:     #(mkFlag vtxSupport    "CONFIG_VTX=y"     libayemu)
    ];
  
    clangGCC = runCommand "clang-gcc" {} ''
      #! ${stdenv.shell}
      mkdir -p $out/bin
      ln -s ${stdenv.cc}/bin/clang $out/bin/gcc
      ln -s ${stdenv.cc}/bin/clang++ $out/bin/g++
    '';
  
  in
  
  stdenv.mkDerivation rec {
  