anchor.diff:  %% @spec code_change(OldVsn, State, Extra) -> {ok, NewState}
   %% @end
   %%--------------------------------------------------------------------
  -code_change(_OldVsn, State, _Extra) ->
  +code_change(OldVsn, State, _Extra) ->
  +    lager:info("Code change request received. Old version: ~p", [OldVsn]),
       {ok, State}.
   
   %%%===================================================================
  
positive.code: %%                                   {stop, Reason, State}
  %% @end
  %%--------------------------------------------------------------------
  handle_info(_Info, State) ->
      {noreply, State}.
  
  %%--------------------------------------------------------------------
  
negative.code: %% @spec terminate(Reason, State) -> void()
  %% @end
  %%--------------------------------------------------------------------
  terminate(Reason, _State) ->
      lager:info("CVMFS auth module terminating with reason: ~p", [Reason]),
      ok.
  
  %%--------------------------------------------------------------------
  