anchor.diff:  # imlib2 can load images from ID3 tags.
   , libid3tag, librsvg, libheif
   , freetype , bzip2, pkg-config
  -, x11Support ? true, xlibsWrapper ? null
  +, x11Support ? true
   , svgSupport ? false
   , heifSupport ? false
   , webpSupport ? false
  
positive.code:   buildInputs = [
      libjpeg libtiff giflib libpng
      bzip2 freetype libid3tag
    ] ++ optional x11Support xlibsWrapper
      ++ optional heifSupport libheif
      ++ optional svgSupport librsvg
      ++ optional webpSupport libwebp
  
negative.code: , openbox
  , fluxbox
  , enlightenment
  , xorg
  }:
  
  let
    inherit (lib) optional optionals;
  in
  stdenv.mkDerivation rec {
    pname = "imlib2";
  