anchor.diff:                end,
       {BuildTime, SyncStruct} =
           util:tc(fun() -> build_recon_struct(ToBuild, OldSyncStruct, DestI,
  -                                            DBList, Params, FinishRecon)
  +                                            DBList, Params, BeginSync)
                   end),
       Stats1 = rr_recon_stats:inc([{build_time, BuildTime}], Stats),
       NewState = State#rr_recon_state{struct = SyncStruct, stats = Stats1},
  -    if FinishRecon ->
  +    if BeginSync ->
              begin_sync(SyncStruct, Params, NewState#rr_recon_state{stage = reconciliation});
          true ->
              NewState % keep stage (at initiator: reconciliation, at other: build_struct)
  
positive.code:     merkle_tree:new(I, DBItems, [{signature_size, SignatureSize},
                                   {branch_factor, BranchFactor},
                                   {bucket_size, BucketSize},
                                   {keep_bucket, not FinishRecon}]);
  build_recon_struct(merkle_tree, OldSyncStruct, _I, DBItems, _Params, FinishRecon) ->
      ?ASSERT(not intervals:is_empty(_I)),
      ?ASSERT(merkle_tree:is_merkle_tree(OldSyncStruct)),
      NTree = merkle_tree:insert_list(DBItems, OldSyncStruct),
      if FinishRecon ->
             % no more DB items -> finish tree, remove buckets
             merkle_tree:gen_hash(NTree, true);
         true ->
             % don't hash now - there will be new items
             NTree
      end;
  build_recon_struct(art, _OldSyncStruct = {}, I, DBItems, _Params = {}, FinishRecon) ->
      ?ASSERT(not intervals:is_empty(I)),
      SignatureSize = get_art_signature_size(),
      BranchFactor = get_merkle_branch_factor(),
  
negative.code:            % more DB items to come... stay with merkle tree
             Tree
      end;
  build_recon_struct(art, OldSyncStruct, _I, DBItems, _Params = {}, BeginSync) ->
      % similar to continued merkle build
      ?ASSERT(not intervals:is_empty(_I)),
      ?ASSERT(merkle_tree:is_merkle_tree(OldSyncStruct)),
      Tree1 = merkle_tree:insert_list(DBItems, OldSyncStruct),
      if BeginSync ->
             % no more DB items -> finish tree, remove buckets, create art struct:
             NTree = merkle_tree:gen_hash(Tree1, true),
             #art_recon_struct{art = art:new(NTree, get_art_config()),
  