anchor.diff:        "--enable-avdevice"
         "--enable-avfilter"
         "--enable-avformat"
  -      (ifMinVer "1.0" (ifVerOlder "5.0" "--enable-avresample"))
  -      (ifMinVer "1.1" "--enable-avutil")
  +      (ifVerOlder "5.0" "--enable-avresample")
  +      "--enable-avutil"
         "--enable-postproc"
         "--enable-swresample"
         "--enable-swscale"
  
positive.code:   postPatch = "patchShebangs .";
    inherit patches;
  
    outputs = [ "bin" "dev" "out" "man" ]
      ++ optional (reqMin "1.0") "doc" ; # just dev-doc
    setOutputFlags = false; # doesn't accept all and stores configureFlags in libs!
  
    configurePlatforms = [];
  
negative.code:       "--enable-libass"
        "--enable-bzlib"
        "--enable-gnutls"
        "--enable-fontconfig"
        "--enable-libfreetype"
        "--enable-libmp3lame"
        "--enable-iconv"
        "--enable-libtheora"
        (ifMinVer "2.1" "--enable-libssh")
        (enableFeature vaapiSupport "vaapi")
  