We forked Apache Stateful Functions for Flink 2.x — here's why

Apache Stateful Functions is one of the quietly powerful frameworks in the Flink ecosystem - durable per-key state, exactly-once messaging, polyglot remote functions, all on top of Apache Flink. It's also been functionally dormant since October 2024 , and it doesn't run on Flink 2.x. We needed it on Flink 2.x. So we maintained the continuation: kzmlabs/flink-statefun . This post is the why and the how it's different . If you're already running upstream and wondering whether to migrate, or you're