anchor.diff:    propagatedBuildInputs = with xorg; with stdenv.lib;
       [ expat glib cairo pango gdk_pixbuf atk at_spi2_atk
         libXrandr libXrender libXcomposite libXi libXcursor libSM libICE ]
  -    ++ optionals stdenv.isLinux [ wayland ]
  +    ++ optionals waylandSupport [ wayland wayland-protocols ]
       ++ optional stdenv.isDarwin (with darwin.apple_sdk.frameworks; [ AppKit Cocoa ])
       ++ optional xineramaSupport libXinerama
       ++ optional cupsSupport cups;
  
positive.code: { stdenv, fetchurl, pkgconfig, gettext, perl
  , expat, glib, cairo, pango, gdk_pixbuf, atk, at_spi2_atk, gobjectIntrospection
  , xorg, wayland, epoxy, json_glib, libxkbcommon, gmp
  , xineramaSupport ? stdenv.isLinux
  , cupsSupport ? stdenv.isLinux, cups ? null
  , darwin
  
negative.code:     "--disable-glibtest"
      "--with-gdktarget=quartz"
      "--enable-quartz-backend"
    ] ++ optional stdenv.isLinux [
      "--enable-x11-backend"
    ] ++ optional waylandSupport [
      "--enable-wayland-backend"
    ];
  
    postInstall = ''
  