anchor.diff:  
   -define(ETS, prop_partisan).
   -define(NAME, fun(Name) -> [{_, NodeName}] = ets:lookup(?ETS, Name), NodeName end).
  +
  +%% @private
  +sleep() ->
  +    RunnerNode = node(),
  +
  +    ?PROPERTY_MODULE:command_preamble(RunnerNode, [sleep]),
  +
  +    node_debug("sleeping for convergence...", []),
  +    timer:sleep(40000),
  +
  +    ?PROPERTY_MODULE:command_conclusion(RunnerNode, [sleep]),
  +
  +    ok.
   
   %% @private
   write(Node, Key, Value) ->
  
positive.code: 
  %% Global functions.
  node_global_functions() ->
      [].
  
  %% What should the initial node state be.
  node_initial_state() ->
  
negative.code: 
  %% Precondition.
  node_precondition(_NodeState, {call, ?MODULE, write, [_Node, _Key, _Value]}) ->
      true;
  node_precondition(_NodeState, {call, ?MODULE, sleep, []}) ->
      true;
  node_precondition(#node_state{values=Values}, {call, ?MODULE, read, [_Node, Key]}) ->
      % node_debug("checking precondition for read operation on key: ~p with values: ~p", [Key, dict:to_list(Values)]),
  