See the 5.0 milestone for details. There are quite some breaking changes, now that we'd destabilize anyway, such as a new zookeeper storageclass and auto.create.topics.enable changed to false.

Kafka 2.1.0 is the first Kafka release with Java 11 support. Previously it was Java 8, while support for Docker containers was greatly improved with Java 10. See https://medium.com/adorsys/jvm-memory-settings-in-a-container-environment-64b0840e1d9e and https://blog.docker.com/2018/04/improved-docker-container-integration-with-java-10/ for background.

We should take the leap sooner rather than later because memory limits with java containers is a huge improvement. Actually it's quite difficult to maintain a production cluster without resource limits on containers. Thus we encourage everyone to try to stabilize on Kafka 2.1.0 + Java 11 in test environments as soon as possible.

If you need a more well tested setup or rely on other tools in the Kafka ecosystem that are not yet available with 2.1+ support, see the v4.3.0 release of this repo.