anchor.diff:                                     PageSize, NumPages * (PageSize * ?PAGE_OVERHEAD)))
        end || X <- lists:seq(1, NumFLUs)].
   
  -append_test() ->
  +smoke1_test() ->
       NumFLUs = 4,
       PageSize = 8,
       NumPages = 10,
       FLUs = [F1, F2, F3, F4] = setup_basic_flus(NumFLUs, PageSize, NumPages),
       {ok, Seq} = corfurl_sequencer:start_link(FLUs),
   
  +    %% We know that the first LSN will be 1.
  +    LPN_Pgs = [{X, list_to_binary(
  +                     lists:flatten(io_lib:format("~8..0w", [X])))} ||
  +                  X <- lists:seq(1, 5)],
       try
           P1 = new_simple_projection(1, 1, 1*100, [[F1, F2], [F3, F4]]),
  -        [begin
  -             Pg = lists:flatten(io_lib:format("~8..0w", [X])),
  -             ok = append_page(Seq, P1, list_to_binary(Pg))
  -         end || X <- lists:seq(1, 5)],
  -
  +        [begin {ok, LPN} = append_page(Seq, P1, Pg) end || {LPN, Pg} <- LPN_Pgs],
  +        [begin {ok, Pg} = read_page(P1, LPN) end || {LPN, Pg} <- LPN_Pgs],
           ok
       after
           corfurl_sequencer:stop(Seq),
  
positive.code:             end;
          Else ->
              %% TODO: corner case
  io:format(user, "WTF? Else = ~p\n", [Else]),
              Else
      end.
  
  flu_pid(X) when is_pid(X) ->
  
negative.code:           r :: [#range{}]
           }).
  
  append_page(Sequencer, P, Page) ->
      append_page(Sequencer, P, Page, 1).
  
  append_page(Sequencer, P, Page, Retries) when Retries < 50 ->
      case corfurl_sequencer:get(Sequencer, 1) of
          LPN when is_integer(LPN) ->
              case write_single_page(P, LPN, Page) of
                  ok ->
                      {ok, LPN};
                  X when X == error_overwritten; X == error_trimmed ->
                      io:format(user, "LPN ~p race lost: ~p\n", [LPN, X]),
                      append_page(Sequencer, P, Page);
                  Else ->
  