public async Task <Guid> Process(Guid preparationId)
        {
            // DO SOMETHING!
            // Lookup preparation, do some processing and persist the result
            var itemId   = Guid.Empty;
            var resultId = Guid.NewGuid();

            // Event notification?
            await publisher.ProcessingCompleted(itemId, resultId).ConfigureAwait(false);

            return(resultId);
        }