default event bus vs custom event bus

Question

When to use default event bus and when to create our own custom event bus ?

Accepted Answer

You use the Default event bus for schedule based rules (although now I recommend using the new EventBridge Scheduler, which does not use any bus) or for events generated by AWS services.

If you create your own application that generates events, I recommend to use a Custom event bus.

Answer

Just in case If you need to have a queue to connect things I would suggest to create one pipe and distinguish destinations by preprocessing using filters, with no additional cost, pay only for events after filtering:  The new feature: EventBridge Pipes https://docs.aws.amazon.com/eventbridge/latest/userguide/eb-pipes-event-filtering.html

Answer

When you need to have different permissions on the bus. Generally, a good idea to have a separate bus https://docs.aws.amazon.com/eventbridge/latest/userguide/eb-event-bus-perms.html

default event bus vs custom event bus

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