# A producer team tries to publish version 5 of the checkout_events schema Canonical URL: Domain: Pipeline Design ยท Difficulty: medium ## Problem A producer team tries to publish version 5 of the checkout_events schema. Version 5 renames amount to amount_cents, which is incompatible with both backward and forward read of the existing topic. Without a registry the rename would land on the topic, every consumer would either read NULL or fail, and the breakage would be discovered in production. The section's fix is to make the registry the gatekeeper: schemas register before publishing, the registry runs a compatibility check, and incompatible schemas are rejected at registration so they never enter the system. Spot the rejected schema by adding a schema registry node between the producer and the Kafka topic whose name states it runs a compatibility check, and add an annotation showing where the v5 schema is rejected. ## Related - [All practice problems](https://datadriven.io/problems) - [Mock interview mode](https://datadriven.io/interview/a-producer-team-tries-to-publish-version-5-of-the-checkoute-00901a0d) - [System Design Interview Questions](https://datadriven.io/data-engineering-system-design) - [Data Engineering Interview Prep Guide](https://datadriven.io/data-engineer-interview-prep) - [Daily Challenge](https://datadriven.io/daily) --- Source: DataDriven (https://datadriven.io). 100% free data engineering interview prep. Live code execution against Postgres 16, Python 3.11, and Spark sandboxes. No paywall, no premium tier, no signup gate.