anchor.diff:  
   %% @doc Safely retrieves a value from a proplist. Throws an error if the specified key does
   %% not exist in the list.
  --spec safe_get(Key::binary(), Proplist::[{binary(), term()}]) -> term().
  +-spec safe_get(Key::binary(), proplists:proplist()) -> term().
   safe_get(Key, Proplist) ->
       {Key, Value} = lists:keyfind(Key, 1, Proplist),
       Value.
  
positive.code: job_join_rows_to_record(Rows) ->
      job_join_rows_to_record(Rows, []).
  
  -spec job_join_rows_to_record(Rows :: [proplist()], [#pushy_job_node{}]) -> #pushy_job{}.
  job_join_rows_to_record([LastRow|[]], JobNodes) ->
      C = proplist_to_job_node(LastRow),
      Job = prepare_pushy_job_record(LastRow),
  
negative.code:          sql_date/1
          ]).
  
  %% job ops
  
  -spec fetch_job(JobId :: object_id()) ->
  