Hi, David has a valid Kafka-specific point regarding Java versions, but I would take a more general spin on this.
The connector dev wiki [1] defines the support matrix between connector and Flink versions. Flink 1.20 only gets patch support, and the same should apply to the relevant connector versions. In this case that means Flink Connector Kafka v3.4 still gets patch support, if there is demand and meaningful fixes. I think we can deviate from that if it makes more sense (e.g. flink-cdc), but supporting multiple major Flink versions introduce complexity and IMO for most connectors would have technical limitations as well, so we cannot expect it to be default. Best, Ferenc [1] https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=231116690#ExternalizedConnectordevelopment-Support On Monday, May 18th, 2026 at 15:08, David Radley <[email protected]> wrote: > Hi Hong, > The reason the Kafka connectors are like this is due to the different Kafka > versions they support. The V3.3 and v3.4 are still supported and support > 1.20. Each recent Kafka connector version is associated with particular > Kafka client version. There has need a lot of discussion on the dev list to > get to this approach. > > I see [1] says Java 17, Java 21, and Java 25 are fully supported while Java > 11 is supported for a subset of modules. Flink 1.20 is still java 8. I think > the way the Kafka connector versions have been done makes sense, it means > that the dependencies are for a particular Kafka client and not more > complicated.. > > Kind regards, David. > > [1] https://kafka.apache.org/42/operations/java-version/ > > From: Hongshun Wang <[email protected]> > Date: Monday, 18 May 2026 at 04:16 > To: [email protected] <[email protected]> > Subject: [EXTERNAL] Re: [VOTE] Release flink-connector-kafka v5.0.0, release > candidate #1 > > Hi Ferenc, > A minor issue — it doesn't block this release, as it has existed since > version 4.0. > I noticed that both flink-sql-connector-kafka/5.0.0-2.1 and > flink-sql-connector-kafka/5.0.0-2.2 are available[1]. Only 2.x is supported. > > Given that Flink 1.20 is the previous LTS (Long-Term Support) version, it > holds more practical value for many users. For example, Flink CDC supports > both Flink 1.20 and 2.x[2]. > Are there any plans to align with this trend and provide broader support > accordingly? （If the current 5.0.0-2.1 can be used with Flink 1.20, should > we provide a documentation note to clarify this?） > > > [1] > https://repository.apache.org/content/repositories/orgapacheflink-1912/org/apache/flink/flink-sql-connector-kafka/5.0.0-2.1/ > [2] > https://flink.apache.org/2026/03/30/apache-flink-cdc-3.6.0-release-announcement/#postgresql > > On Fri, May 15, 2026 at 10:51 PM Gabor Somogyi <[email protected]> > wrote: > > > +1 (binding) > > > > - Downloaded all artifacts > > - Fetched sources and compiled with JDK17 + Maven 3.8.6 > > - Diff of git tag checkout with downloaded sources > > - Verified SHA512 checksums & GPG certification > > - Checked that all POMs have the right expected version > > - Generated diffs to compare pom file changes with NOTICE files > > > > G > > > > > > On Tue, May 12, 2026 at 11:51 PM Ferenc Csaky <[email protected]> wrote: > > > > > Hi everyone, > > > > > > Please review and vote on release candidate #1 for flink-connector-kafka > > > v5.0.0, as follows: > > > [ ] +1, Approve the release > > > [ ] -1, Do not approve the release (please provide specific comments) > > > > > > > > > The complete staging area is available for your review, which includes: > > > * JIRA release notes [1], > > > * the official Apache source release to be deployed to dist.apache.org > > > [2], which are signed with the key with fingerprint 16AE0DDBBB2F380B [3], > > > * all artifacts to be deployed to the Maven Central Repository [4], > > > * source code tag v5.0.0-rc1 [5], > > > * website pull request listing the new release [6]. > > > * CI build of the tag [7]. > > > > > > The vote will be open for at least 72 hours. It is adopted by majority > > > approval, with at least 3 PMC affirmative votes. > > > > > > Thanks, > > > Ferenc > > > > > > [1] > > > > > https://issues.apache.org/jira/secure/ReleaseNote.jspa?projectId=12315522&version=12356170 > > > [2] > > > > > https://dist.apache.org/repos/dist/dev/flink/flink-connector-kafka-5.0.0-rc1 > > > [3] https://dist.apache.org/repos/dist/release/flink/KEYS > > > [4] > > > https://repository.apache.org/content/repositories/orgapacheflink-1912/ > > > [5] > > > https://github.com/apache/flink-connector-kafka/releases/tag/v5.0.0-rc1 > > > [6] https://github.com/apache/flink-web/pull/849 > > > [7] > > > https://github.com/apache/flink-connector-kafka/actions/runs/25763016618 > > > > > > > Unless otherwise stated above: > > IBM United Kingdom Limited > Registered in England and Wales with number 741598 > Registered office: Building C, IBM Hursley Office, Hursley Park Road, > Winchester, Hampshire SO21 2JN >
