Kafka Monthly Digest: November 2025

Releases

4.1.1

4.2.0

3.9.2

Kafka Improvement Proposals

• KIP-1239: Batch offset translation in RemoteClusterUtils: When using MirrorMaker and the MirrorCheckpointConnector, the RemoteClusterUtils.translateOffsets() API allows users to manually translate consumer group offsets between clusters. This API takes a single consumer group Id as input. However this can be an expensive call as it requires reading the entire checkpoints topic. This KIP proposes allowing to translate the offsets of multiple consumer groups in a single call since the full topic has to be processed anyway.
   

• KIP-1243: Consistent Metadata Reads: Kafka clients automatically send calls to the appropriate brokers. Calls that can be sent to any brokers are sent to the least loaded broker (from the client's point of view). This means that a call that updates metadata, followed by a call that reads metadata can be sent to different brokers. Because brokers reply from their metadata cache, it is not guarantees that the second call (the read) will see the impact of the first one (the write). This KIP aims at providing consistent reads by having clients and brokers exchange tokens that help identify the latest metadata version they are aware of.
   

• KIP-1244: Drop support for streams-scala in Kafka 5.0 (deprecate in 4.3): The streams-scala package was introduced in Kafka 2.0. It provides an idiomatic API for Streams to Scala users. Several years later, this package has a relatively low adoption rate within the Streams user base and it has not been updated to support Scala 3. The intention of this KIP is to determine the future of the streams-scala package. 
   

Community Releases

• strimzi-kafka-operator 0.49: Strimzi is a Kubernetes Operator for running Kafka. This new version introduces v1 APIs for all the CRDs in preparation for Strimzi 1.0. The older APIs are supported till Strimzi 0.52 and there is a conversion tool to convert and upgrade existing CRDs. This release adds support for Kafka 4.0.1 and 4.1.1. It now also supports Buildah to build custom Kafka Connect images.
   

• kroxylicious 0.18.0: Kroxylicious is an open source pluggable framework for writing network proxies that understand the Apache Kafka protocol. This versions adds an Authorizer API with a built-in implementation to perform authorizations in the proxy. It also introduces SASL and transport Subject builder APIs to derive user identities from SASL and TLS.
   

Blogs

• Colocating Input Partitions with Kafka Streams When Consuming Multiple Topics: Sub-Topology Matters!
• KIP-1150 Diskless Topics cost savings compared to Confluent Freight
• From JSON to AVRO in the CDC pipeline
• Replication redefined: How we built a low-latency, multi-tenant data replication platform