The interviewer asked me to design Amazon order tracking

Definition

The tweet is a postmortem-style interview lesson: the author admitted overengineering a design by diving into Kafka before defining core requirements and users. It emphasizes starting with requirements—who consumes tracking data (customer, seller, support, carrier ops)—and designing for clear read paths over write paths. They outline practical architecture: order/shipments/tracking events model, API surfaces for current status and event timelines, idempotent carrier ingest, and a projection-based read model for fast status retrieval. They also stress correctness constraints like non-regressive statuses, event ordering per shipment, dedupe/idempotency, GDPR-like deletion concerns, and observability/failure scenarios.

Sources

• raw/Tech/2026-07-01-0xlelouch_-interviewer-asked-me-to-design-amazon-order-tracking.md