anchor.diff:    postPatch = "patchShebangs .";
     inherit patches;
   
  -  outputs = [ "bin" "dev" "out" "man" ]
  -    ++ optional (reqMin "1.0") "doc" ; # just dev-doc
  +  outputs = [ "bin" "dev" "out" "man" "doc" ];
     setOutputFlags = false; # doesn't accept all and stores configureFlags in libs!
   
     configurePlatforms = [];
  
positive.code:       (ifMinVer "4.2" (enableFeature libaomSupport "libaom"))
        (lib.optionalString pulseaudioSupport "--enable-libpulse")
        (ifMinVer "2.5" (if sdlSupport && reqMin "3.2" then "--enable-sdl2" else null))
        (ifMinVer "1.2" "--enable-libsoxr")
        "--enable-libx264"
        "--enable-libxvid"
        "--enable-libzimg"
  
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")
  