anchor.diff:      int_post_block(Block, State),
       {next_state, waiting_for_keys, State}.
   
  +-spec int_post_block(#block{}, #state{}) -> ok | new_top | error.
   int_post_block(Block,_State) ->
       epoch_mining:info("write_block: ~p", [Block]),
       Header = aec_blocks:to_header(Block),
  
positive.code:         new_top ->
              start_if_auto(State),
              {next_state, configure, State};
          ok ->
              {next_state, configure, State}
      end.
  
negative.code:         new_top ->
              start_if_auto(State),
              {next_state, configure, State};
          error ->
              {next_state, running, State};
          ok ->
              epoch_mining:info("Post block not on top of chain"),
              {next_state, running, State}
  