Apache Kafka 3.4 introduces numerous new features and improvements, with a key highlight being the early access capability to migrate Kafka clusters from ZooKeeper to KRaft mode without downtime, although this is not yet recommended for production use. The update includes KIP-866, which facilitates this migration by transferring cluster metadata to the KRaft metadata log, allowing brokers to restart in KRaft mode one at a time. Other notable updates include KIP-792, which enhances metadata sharing for partition assignments, and KIP-854, which optimizes producer ID cleanup to improve memory usage. Additionally, KIP-881 extends rack-awareness for partition assignments, though its practical application requires a custom assignor. The release also includes numerous configuration updates, such as the deprecation of certain parameters and the introduction of new settings for better resource management and monitoring. Overall, Apache Kafka 3.4 is a community-driven effort that aims to enhance the platform's scalability, reliability, and integration capabilities, with contributions from a large number of developers.