Keep the order story consistent across systems.

The store accepts an order while stock is managed elsewhere. Staff copy records, correct product identifiers and investigate mismatched quantities. A delayed update can affect both the customer promise and the warehouse workload.

Choose the source of truth for products, stock and order status. Map identifiers and define which events move information between systems. Separate the receipt of an event from the completion of fulfillment.

An order event can arrive twice or out of sequence. Use stable identifiers and reconciliation rather than treating every message as a new order. Conflicting stock or unsupported status changes should reach an operator.

Agree stock reservations, partial shipments, returns, cancellations and the frequency of updates. API limits and operational rules determine what can be synchronized safely.