anchor.diff:  , debugDeveloper ? false
   , optimizationsDeveloper ? true
   , extraWarningsDeveloper ? false
  -# Darwin frameworks
  -, Cocoa
   # Inherit generics
  -, branch, sha256, version, ...
  +, branch
  +, sha256
  +, version
  +, ...
   }:
   
   /* Maintainer notes:
  
positive.code:  *
   */
  
  let
    inherit (stdenv) icCygwin isDarwin isFreeBSD isLinux;
    inherit (stdenv.lib) optional optionals enableFeature;
  
    cmpVer = builtins.compareVersions;
    reqMin = requiredVersion: (cmpVer requiredVersion branch != 1);
    reqMatch = requiredVersion: (cmpVer requiredVersion branch == 0);
  
negative.code:       "--enable-libmp3lame"
        (ifMinVer "1.2" "--enable-iconv")
        "--enable-libtheora"
        (ifMinVer "0.6" "--enable-vaapi")
        "--enable-vdpau"
        "--enable-libvorbis"
        (ifMinVer "0.6" "--enable-libvpx")
        (ifMinVer "2.4" "--enable-lzma")
        (ifMinVer "2.2" (enableFeature openglSupport "opengl"))
        (ifMinVer "0.9" "--enable-libpulse")
        (ifMinVer "2.5" "--enable-sdl") # Only configurable since 2.5, auto detected before then
        (ifMinVer "1.2" "--enable-libsoxr")
        "--enable-libx264"
  