Apicurio Registry vs Karapace
Apicurio Registry
apicur.ioKarapace
aiven.ioSide by side
| Figure | Apicurio Registry | Karapace |
|---|---|---|
| Price from | — | $35/mo |
| Free plan | — | Yes |
| Free trial | — | — |
| Open source | — | — |
| Web | Yes | — |
| Windows | Yes | — |
| macOS | Yes | — |
| Linux | Yes | Yes |
| API | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 0 | 2 |
| Spec score · Schema Registry Software | 8.0 (#11) | 8.1 (#8) |
| Authentication | Documented authentication options include OpenID Connect, HTTP basic, proxy header, and Kubernetes-native authentication; authentication and authorization options are disabled by default. | Karapace supports OAuth 2.0/OIDC authentication for Schema Registry and the REST Proxy. |
| Authorization | Authorization options include default admin, write, and read-only roles, plus content-based controls that can restrict artifact updates or deletion to its owner. | Schema Registry authorization uses access control lists, and OIDC role-based authorization can restrict operations by HTTP method. |
| Deployment | The getting-started guide runs the server and UI as separate Docker images and also names Podman as a prerequisite option. | The project documents Docker-based setup and installation from source with pip. |
| Integrations | The documentation describes Kafka client serializers and deserializers for Avro, Protobuf, and JSON Schema, and integration with Kafka Connect. | The Aiven Terraform Provider supports managing Karapace Schema Registry authorization ACL entries. |
Plans
In their own words
Apicurio Registry
Apicurio Registry is an open-source runtime server for storing API designs and schemas as artifacts. Users can add, update, and remove artifacts through a remote REST API. For API discovery, teams can register designs such as OpenAPI, AsyncAPI, and GraphQL so consumers can search and browse APIs, see details, and read generated documentation. For messaging and event streaming, it provides a central place to track schemas and manage data-format evolution. Supported artifact types include OpenAPI, AsyncAPI, GraphQL, Apache Avro, Protocol Buffers, JSON Schema, Kafka Connect schema, WSDL, XML Schema, and ODCS v3.1. Configurable rules can check validity, compatibility, and integrity as artifacts change. Listed storage backends include Apache Kafka, PostgreSQL, and Microsoft SQL Server. Management options include a web console, REST API, command line, Maven plug-in, and Java client. Kafka serializers and deserializers can enforce schemas in producer and consumer applications. The documentation covers self-hosted deployment, including Kubernetes. The quick-start in-memory server is non-persistent and is not intended for production.
Karapace
Karapace is Aiven’s open-source Schema Registry and REST Proxy for Aiven for Apache Kafka. The registry stores and versions schemas, then checks compatibility before a changed schema is published. It accepts Avro, Protobuf, and JSON Schema, with references supported for Avro and Protobuf. Compatibility modes include NONE, BACKWARD, BACKWARD_TRANSITIVE, FORWARD, FORWARD_TRANSITIVE, FULL, and FULL_TRANSITIVE. The REST Proxy exposes HTTP endpoints for producing and consuming Kafka events, so scripts, curl, and HTTP services can work with events. OAuth 2.0/OIDC authentication is available for both components. Registry ACLs and OIDC role-based rules can limit operations, including by HTTP method. Example identity providers include Auth0, Okta, Google Identity Platform, and Azure. Deployment documentation covers Docker and installation from source with pip; the API is stated to support Schema Registry 6.1.1 operations. Karapace is available in Aiven’s Kafka free tier for learning, prototyping, and evaluation. The Free plan costs nothing, while Developer costs $35 a month.