Transactional messaging

[sgc109]

Hi, I'm just a developer who is researching Axon and found out your awesome project, and I got to be curious about how you were going to handle transactional messaging.
In the diagram of README I can see command handlers are publishing events to both Kafka and MongoDB. As far as I know, we should use transactional messaging(e.g. by using outbox pattern) to make sending events to more than one components(i.e. Kafka and MongoDB in this case) to be atomic. Could I ask you how you were going to handle it?

Thank you!