Hi, Cooper. Thank you for bringing up the discussion about Kafka 4.0.0. I tend to release Kafka Connector 4.0 with Flink 2.0.0 and Kafka 3.9.0, or Kafka 3.8.1 if If the community is concerned about 3.9.0.
Here are some of my opinions: 1. The plan for Kafka Connector 4.0.0 was proposed[1] a long time ago, mainly to support the Flink 2.0 API. Although it has been delayed for some time, users' demand for this version is becoming increasingly strong (as we can see from emails or Slack), so it is more important to release a version that supports Flink 2.0 as soon as possible. 2. For Bump to Kafka 4.0.0, I personally believe that this is a decision that requires careful analysis, because rolling back to Kafka client version 3. x will require additional workload, and the impact on performance and API compatibility may not be reflected solely through IT cases(Of course, I believe it will have a positive impact). I don't recommend making two major changes in one version,So perhaps 4.1/5.0 is more suitable for doing this. 3. As for Kafka 3.9.0, I don't have a big opinion as we have been using Kafka client 3.4.0 for almost two years since FLINK-31599[2]. Of course, I also approve of using Kafka 3.8.1. But for using 3.9.1, the benefits are not very significant and it will block the activities of other developers who rely on Flink connector Kafka release 4.0. As I know, some e2e in Flink rely on Kafka connectors, but they have been temporarily removed[3], and development activities[4] for Apache Paimon adaptation to Flink 2.0, etc. Best, Yanquan. [1]https://lists.apache.org/thread/rl7prqop7wfn2o8j2j9fd96dgr1bjjnx [2]https://issues.apache.org/jira/browse/FLINK-31599 [3]https://issues.apache.org/jira/browse/FLINK-36413 [4]https://github.com/apache/paimon/issues/5350 > 2025年4月1日 22:50，Tom Cooper <c...@tomcooper.dev> 写道： > > Kafka 4.0.0
