anchor.diff:  , opencv4
   , openexr
   , openh264
  +, libopenmpt
   , pango
   , rtmpdump
   , sbc
  
positive.code:     # is needed, and then patching upstream to find it (though it probably
      # already works on Arch?).
      "-Dmusepack=disabled"
      "-Dopenmpt=disabled" # `libopenmpt` not packaged in nixpkgs as of writing
      "-Dopenni2=disabled" # not packaged in nixpkgs as of writing
      "-Dopensles=disabled" # not packaged in nixpkgs as of writing
      "-Dsctp=disabled" # required `usrsctp` library not packaged in nixpkgs as of writing
  
negative.code:     mpeg2dec
      libmicrodns
      openjpeg
      libopenmpt
      libopus
      librsvg
      curl.dev
  