diff --git a/pkgs/development/python-modules/pyglet/default.nix b/pkgs/development/python-modules/pyglet/default.nix
index e303f3415d7..1e7beddda7f 100644
--- a/pkgs/development/python-modules/pyglet/default.nix
+++ b/pkgs/development/python-modules/pyglet/default.nix
@@ -43,6 +43,8 @@ buildPythonPackage rec {
                 path = '${gtk2-x11}/lib/libgdk-x11-2.0${ext}'
             elif name == 'gdk_pixbuf-2.0':
                 path = '${gdk-pixbuf}/lib/libgdk_pixbuf-2.0${ext}'
+            elif name == 'Xext':
+                path = '${xorg.libXext}/lib/libXext${ext}'
             if path is not None:
                 return ctypes.cdll.LoadLibrary(path)
         raise Exception("Could not load library {}".format(names))