diff --git a/util.lua b/util.lua
index 09cf576..6a024bc 100644
--- a/util.lua
+++ b/util.lua
@@ -20,6 +20,9 @@ util.TransientUser = {
   is_guest = function (self)
     return true
   end,
+  is_system = function (self)
+    return false
+  end,
   is_logged_in_guest = function (self)
     return false
   end,