The fourth Kafka meetup was co-hosted by Aiven and Zalando at Zalando's Helsinki office. Topics discussed included Nakadi, a distributed event bus with RESTful API built on top of Kafka; Bubuku, a tool created by Zalando for making their operations of Kafka easier; and Debezium, which uses logical replication to replicate a stream of changes to a Kafka topic. The meetup provided valuable insights into tools that can enhance the use of Apache Kafka.