AWS Glue Schema Registry vs Buf Schema Registry

AWS Glue Schema Registry is a free cloud service for centrally discovering, controlling, and evolving schemas used by streaming applications. It supplies serializers and deserializers so producers and consumers can share schema definitions during data exchange. Supported formats are Avro v1.11.4, JSON Schema Draft-04, Draft-06, and Draft-07, plus Protocol Buffers proto2 and proto3; Protobuf extensions and groups are not supported. Eight compatibility modes are available: NONE, DISABLED, BACKWARD, BACKWARD_ALL, FORWARD, FORWARD_ALL, FULL, and FULL_ALL. Features include automatic registration, metadata-based schema sourcing, IAM compatibility, and optional ZLIB compression. Documented integrations cover Apache Kafka, Amazon MSK, Kinesis Data Streams, Amazon Managed Service for Apache Flink, AWS Lambda, AWS Glue streaming, and Apache Kafka Streams. Client API traffic uses TLS over HTTPS, and schemas are encrypted at rest with an AWS KMS service-managed key. Registry ARNs organize permissions for schema operations.

Buf Schema Registry (BSR) is a Protobuf-aware registry for managing API schemas, dependencies, and client access as APIs change. Teams publish Protobuf files as versioned modules and resolve dependencies declared in buf.yaml. BSR generates hosted SDKs for supported languages and browsable documentation from schema versions and comments. Server-side lint and breaking-change policies can reject updates or hold them for review. The registry also shows which modules depend on another, helping teams identify affected consumers before deprecation. A GitHub Action handles build, lint, formatting, breaking-change checks, and publishing; the Buf CLI can connect to other CI/CD systems. RPC APIs are available through Connect, gRPC, and gRPC-Web. Community costs nothing and includes one private repository limited to 100 types plus unlimited public repositories. Teams costs $0.50 a month per type and includes a 30-day trial. Pro costs $5 a month per type with a $3000/month minimum spend. Enterprise pricing is custom.