Skip to content

Design a Distribution Center Inventory Service

Published 3 October 2026

Problem statement

The system design problem asked for a service that continuously receives inventory updates from distribution centers.

For each combination of:

  • Distribution-center location
  • Item

the service should maintain the latest inventory state. Clients should be able to quickly retrieve information such as:

  • Current quantity
  • Whether the item is available
  • Timestamp of the latest update

The expected scale included thousands of locations, millions of items, and tens of thousands of inventory updates per second. The interviewer pushed into several distributed-system concerns, including consistency, duplicate events, out-of-order updates, partitioning, horizontal scaling, and retaining historical inventory data for analytics.