Right now: kcctl [1], a command-line client for Kafka Connect. Using the REST API just became to unwieldy when demoing Debezium. Quite a while ago, MapStruct [2], a code generator for type-safe mapper classes for converting POJOs (Java object) between object hierarchies which are similar but not quite the same. It was born after realizing that significant time in an enterprise application I was working on back in the day was spent executing reflection-based mapping code.
[1] https://github.com/kcctl/kcctl [2] https://mapstruct.org/