Integration events: emit → fan-out → deliver

A domain event flows through the Hub to every subscribed integration, best-effort, without ever affecting the operation that emitted it.

End-to-end

Subscription matching

An integration matches when it is active, in the event's tenant/merchant scope, subscribed to the event type, and either scope-wide (campaign_id == "") or narrowed to the event's campaign.

Register + test

Proven by make e2e-integration: register an sms integration, emit prize_won → dispatched: 1; emit an unsubscribed event → dispatched: 0; delete it → dispatched: 0.