anchor.diff:  put_entity(Name, node, Value) ->
       value_check(node, Value),
       IdGroup = wallaby_node:identity_group(Value),
  -    Whence = canonicalize_hash(put_entity(IdGroup, group, wallaby_group:new(IdGroup))),
  +    Whence = wallaroo_hash:canonicalize(put_entity(IdGroup, group, wallaby_group:new(IdGroup))),
       gen_server:call(?SERVER,  {put, node, Name, Value, Whence});
   put_entity(Name, Kind, Value) when ?VALID_ENTITY_KIND(Kind) ->
       value_check(Kind, Value),
  
positive.code:     put_branch(Name, Commit, [], []).
  
  put_branch(Name, C, Anno, Meta) ->
      Commit = canonicalize_hash(C),
      gen_server:call(?SERVER,  {put_branch, Name, Commit, Anno, Meta}).
  
  put_tag(Name, C) ->
      put_tag(Name, C, [], []).
  
  put_tag(Name, C, Anno, Meta) ->
      Commit = canonicalize_hash(C),
      gen_server:call(?SERVER,  {put_tag, Name, Commit, Anno, Meta}).
  
  value_check(node, {wallaby_node, _}) ->
  
negative.code: %%% Helpers
  
  add_last_updated(Commit, {value, {wallaby_node, Dict}}) ->
      {value, {wallaby_node, orddict:store(last_updated_version, list_to_binary(wallaroo_hash:stringize(Commit)), Dict)}};
  add_last_updated(_, _=Val) ->
      Val.
  
  xlate_what('node') ->
      <<"nodes">>;
  