anchor.diff:      harfbuzz_lib
       libpng
       libx11
  +    libxcb
       libxcursor
       libxi
       libxinerama
  
positive.code:     opengl-dummy
      wayland
      wayland-protocols
    ];
  
    postPatch = ''
      # Don't build docs.
      mkdir -pv docs/_build/html
      sed -i setup.py \
        -e '/copy_man_pages(ddir)$/d' \
        -e '/copy_html_docs(ddir)$/d'
  
negative.code: , opengl-dummy
  , wayland
  , wayland-protocols
  , zlib
  }:
  
  let
  