Preparing Apache Kafka® for Scala 3

The Open Source Program Office (OSPO) at Aiven recently undertook the task of migrating Apache Kafka to Scala 3, a strong statically typed programming language that combines object-oriented and functional programming paradigms. This migration was necessary as older versions of libraries and languages eventually stop receiving updates, making them vulnerable to new security threats and incompatible with newer technologies. The process involved several challenges such as the build tool not supporting Scala 3 yet, issues related to syntax changes between Scala 2 and 3, too many automatic conversions, and problems with bytecode generation. Despite these hurdles, Aiven successfully completed the migration, which will help keep Apache Kafka up-to-date with security patches and performance improvements.