What is Schema Registry?

Confluent Schema Registry is a centralized repository for Avro, JSON Schema, and Protobuf schemas used by Kafka topics. It enforces schema compatibility rules (backward, forward, full) so that producers and consumers can evolve schemas without breaking each other. Each schema gets a numeric ID; the producer stores just the schema ID and the compact binary payload (not the full schema per message). The consumer fetches the schema by ID to deserialize. This is the standard way to enforce data contracts in Kafka.

Expected key concepts: Schema Registry, Avro, Protobuf, JSON Schema, compatibility, backward, forward, schema ID, compact binary, data contracts