Outbox Pattern:?

Short answer: Services store the event in the same database as their main transaction, and an external service or process reads from the outbox and publishes the event. This ensures that transactions are consistent and events are only sent once.

Real-world example (ShopNest)

ShopNest splits Catalog, Cart, Order, and Payment into services so teams can deploy catalog changes without redeploying payments.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.