anchor.diff:  %% See {@link dns_query_handler_behaviour} for reference.
   %% @end
   %% ====================================================================
  --spec handle_soa(Domain :: string()) -> {ok, [Response]} | serv_fail | nx_domain | not_impl | refused
  -    when Response :: {MName :: string(), RName :: string(), Serial :: integer(), Refresh :: integer(),
  -    Retry :: integer(), Expiry :: integer(), Minimum :: integer()}.
  +-spec handle_soa(Domain :: string()) -> {reply_type(), dns_query_handler_reponse()} | reply_type().
   %% ====================================================================
   handle_soa(_Domain) -> not_impl.
   
  
positive.code: %% parse_domain/1
  %% ====================================================================
  %% @doc Split the domain name into prefix and suffix, where suffix matches the
  %% canonical provider's hostname (retrieved from env). The split is made on the dot between prefix and suffix.
  %% If that's not possible, returns unknown_domain.
  %% @end
  %% ====================================================================
  
negative.code: %% See {@link dns_query_handler_behaviour} for reference.
  %% @end
  %% ====================================================================
  -spec handle_wks(Domain :: string()) -> {reply_type(), dns_query_handler_reponse()} | reply_type().
  %% ====================================================================
  handle_wks(_Domain) -> not_impl.
  
  