anchor.diff:  
     src = fetchurl {
       url = "mirror://gnome/sources/clutter/${channel}/${name}.tar.xz";
  -    sha256Url = "mirror://gnome/sources/clutter/${channel}/${name}.sha256sum";
  +    hashOutput = false;
       inherit (source) sha256;
     };
   
  
positive.code:     "--disable-installed-tests"
      "--disable-always-build-tests"
      "--disable-examples"
      (wtFlag "x" (xorg != null) null)
    ];
  
    meta = with stdenv.lib; {
      description = "Library for creating graphical user interfaces";
  
negative.code:   configureFlags = [
      "--enable-glibtest"
      "--enable-Bsymbolic"
      "--${boolEn (xorg != null)}-x11-backend"
      "--disable-win32-backend"
      "--disable-quartz-backend"
      "--enable-gdk-backend"
      "--${boolEn (wayland != null)}-wayland-backend"
      "--enable-egl-backend"
      "--disable-mir-backend"
      "--disable-cex100-backend"
      # TODO: tslib, touch screen support
      "--disable-tslib-input"
      "--enable-evdev-input"
      "--${boolEn (wayland != null)}-wayland-compositor"
      "--${boolEn (xorg != null)}-xinput"
      "--${boolEn (gdk-pixbuf != null)}-gdk-pixbuf"
      "--disable-debug"
      "--disable-deprecated"
      "--disable-maintainer-flags"
      #"--disable-Werror"
      "--disable-gcov"
      "--${boolEn (gobject-introspection != null)}-introspection"
      "--disable-gtk-doc"
      "--disable-gtk-doc-html"
      "--disable-gtk-doc-pdf"
  