Choreography vs. Orchestration

1. The Question: Who Coordinates?

A business process rarely fits in one service. Placing an order means reserving inventory, charging payment, creating a fulfillment record, and notifying the customer. That is four services and one logical flow. Something has to make sure every step actually happens.

There are exactly two ways to arrange that. Either one service owns the flow, or nobody does. Those two options have names, and "choreography vs. orchestration" is one of the most reliably asked microservices interview questions.

Choreography: no coordinator