Karapace vs Lenses

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.

Lenses describes its Operating Fabric as a platform for building, governing, and operating Kafka applications with engineers and AI agents. Users can discover streaming data across domains with SQL, prepare it for consumption, and deploy data streams independently. It connects to Confluent Platform, Confluent Cloud, Amazon MSK, Redpanda, and self-managed Apache Kafka, and can run in cloud, on-premises, or hybrid environments. Work interfaces include a Web App, VS Code Extension, Lenses MCP, and Lenses CLI. Lenses says OAuth 2.1 gives agents scoped, short-lived, revocable, and audited access. It also lists open-source Kafka connectors for systems including Amazon S3, Azure Event Hubs, GCP Storage, Cassandra, MongoDB, Redis, and Elasticsearch; the connectors are Apache 2.0 licensed and have enterprise support. The DevX Community Edition supports up to five free users, while SQL Studio supports up to two Kafka clusters. A trial key is available through the guided demo. Team Edition is listed from $4,000 per year and supports up to 15 users with SSO/SAML, RBAC, and Team Support.