   use GenServer
   require Crdtex.Set
 
-  defstruct node_set: Crdtex.Set.new, up_set: MapSet.new, payload: nil, counter: 0, callback: nil
+  defstruct(
+    node_set: Crdtex.Set.new,
+    up_set: MapSet.new,
+    forced_down: Crdtex.Set.new,
+    payload: nil,
+    counter: 0,
+    callback: nil)
 
   defmacro __using__(_), do: []
 

        {:noreply, ring}
      true ->
        new_up_set = MapSet.delete(ring.up_set, n)
        {:ok,new_node_set} = delete(ring.node_set,{node(),ring.counter + 1},n)
        {ring, _} =
         update_ring(%GenServerring{ring | up_set: new_up_set},
           %{node_set: new_node_set, payload: ring.payload, from_node: []})

    old_payload = ring.payload
    ring =
      gen_ring(merged_node_set, up_set, merged_payload, updated_counter,
        ring.callback, merged_forced_down)
    {ring, notify_payload(value(old_payload), value(changes.payload), ring)}
  end

