lukastymo.com/posts/028-st...

Congrats to Kirk True for becoming our latest committer!

While we are slowly heading into 4.3.0 release, we have some other good news for you:

Over the last weeks, we released 3.9.2, 4.0.2, and 4.1.2 bug-fix releases!

Thanks for all 57/44/39 contributors and our RMs PoAn Yang, Viktor Somogyi-Vass, and Andrew Schofield.

We are happy to announce that Viktor Somogyi-Vass accepted our invitation to join the PMC.

Congratulations Viktor!

We are happy to announce that Andrew Schofield accepted our invitation to join the PMC.

Congratulations Andrew!

We are happy to announce that Christo Lolov accepted our invitation to join the PMC.

Congratulations Christo!

We are happy to announce that Kamal Chandraprakash accepted our invitation to join the PMC.

Congratulations Kamal!

We are happy to announce that Lianet Magrans accepted our invitation to join the PMC.

Congratulations Lianet!

Fixed

Curious to see where we will go next!

In the meantime: checkout “streams” groups and let us know what you think!

It’s also a release with major code changes for KS broker side, ie, adding task assignment logic to the group coordinator.

While brokers did get smaller features for KS in the past, the only major feature designed with KS in mind in the past were transactions.

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The recent 4.2 release is one of the largest milestones for Kafka Streams so far. The new “streams” groups introduce Kafka Streams specific RPCs into the protocol, making Kafka Streams more than just a wrapper around consumer/producer clients, and a first class citizen.

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We are happy to announce Apache Kafka 4.2.0!

Highlights are: Queues for Kafka and the new #KafkaStreams "streams" groups.

Thanks to all the 155 contributors and our RM Christo Lolov.

More details on the web page:
kafka.apache.org/blog/2026/01...

Souquieres Adam – Medium Read writing from Souquieres Adam on Medium. Writing about production streaming and data systems. Focus on trade-offs, not trends. Experience-based, not promotional.

Great stuff about Kafka Streams! Check it out!

medium.com/@souquieres....

There is a new KIP-1244 proposing to deprecate the Kafka Streams Scala API, and remove it with the next major release.

Please join the discussion on the dev mailing list if this concerns you.

🚀 I've built a new interactive simulation of #Kafka Streams, showcasing state stores!

See state stores being restored, switch between RocksDB & in-memory state store behavior,restart tasks. Great for understanding or explaining Kafka Streams!

Try it here: kafkastreamsfieldguide.com/tools/state-...

Apache Kafka Apache Kafka: A Distributed Streaming Platform.

We are happy to share that the Apache Kafka 4.1.1 bug-fix release is now available!

It contains a critical memory-leak fix for #KafkaStreams and many other fixes. For details see kafka.apache.org/blog#apache_...

Thanks to 32 contributors and Lianet Magrans as our RM.

Colocating Input Partitions with Kafka Streams When Consuming Multiple Topics: Sub-Topology Matters! Understanding how sub-topology design influences partition co-location

Sub-topologies and co-partitioning are imported concepts. Nice blog post from Expedia:

medium.com/expedia-grou...

Apache Kafka Apache Kafka: A Distributed Streaming Platform.

We are excited to announce the Apache Kafka 4.0.1 bug-fix release, containing over 40 fixes!

Thanks to 53 contributors and your RM Christo Lolov.

For more details, checkout the announcement:
kafka.apache.org/blog#apache_...

🚨Kafka Streams 4.1.0 contains a memory leak regression bug: issues.apache.org/jira/browse/...

Be careful upgrading, or wait for 4.1.1 bug-fix release. We plan to get it out quickly.

Any KIP-1071 experience out there?

Asking for a friend.

🚨 Breaking News from Community Over Code 🚨

Introducing The ASF’s New Logo buff.ly/DzgT82w

#CommunityOverCode #opensource

Apache Kafka Apache Kafka: A Distributed Streaming Platform.

Apache Kafka 4.1.0 was release!

Most exciting, the new “streams” rebalance protocol is available as early access.

We are happy to announce the Apache Kafka 4.1.0 release!

Please try it out, and let us know how it goes!

kafka.apache.org/blog#apache_...

While we are waiting for Apache Kafka 4.1.0 release, the development does not stop. We just completed KIP-1034 (cwiki.apache.org/confluence/d...) which adds a DLQ feature to Kafka Streams. Very exciting!

Next at #Current25 a panel discussion on the past, present and future of @kafkastreams.bsky.social. I love the background...the likeness is uncanny...

Apache Kafka 3.9.1 is now available for download: buff.ly/5ONjJgB

This bug-fix release has several fixes, and most importantly, it adds Java 23 support. #opensource

There is a few more others which are more minor. So we stick with these highlights for now. If you want to know them all (also for older releases), check out the wiki: cwiki.apache.org/confluence/d...

That’s a wrap!

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KIP-1112: cwiki.apache.org/confluence/d...

Injecting custom boiler plate code into all Processors is now easily possible, via this new “processor wrapper” concept. Useful for PAPI users, but invaluable for the DSL!

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KIP-1106: cwiki.apache.org/confluence/d...

This is a shared KIP for the consumer and Kafka Streams. A new auto.offset.reset policy “by duration” is added. Very useful for tiered storage setups when you don’t want to use “earliest” but still want to start at some point in the past.

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KIP-1104: cwiki.apache.org/confluence/d...

Foreign-key table-table joins are very popular. However, the FK could only be extracted from the value so far. This unnecessary limitation is gone now, by passing in both key and value into the FK-key extractor.

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