AWS Glue Schema Registry vs AxonOps 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.

AxonOps Schema Registry is a free, Apache 2.0-licensed service for managing Apache Kafka schemas as an API-compatible replacement for Confluent Schema Registry. It handles Avro, Protobuf, and JSON Schema, including references and seven compatibility modes. Schemas can be stored in PostgreSQL, MySQL, or Cassandra, without requiring Kafka as the storage backend. The project says existing Confluent serializers and Java, Go, and Python Kafka clients can connect by changing the registry URL. Security options include Basic Auth, API keys, JWT, LDAP/AD, OIDC, mTLS, four RBAC roles, rate limiting, and TLS certificate auto-reload. Audit events can go to stdout, files, syslog, or webhooks. Client-side field encryption supports DEK/KEK registries and HashiCorp Vault or OpenBao Transit. Data contracts add metadata and rules. A beta MCP server supports several AI clients. It runs self-hosted on Linux, as a Docker container, or from source.