Kafka Streams vs @KafkaListener @KafkaListener is a consumer — it reads records and processes them one by one or in batches. Kafka Streams is a stream processing library — it builds a topology of transformations that runs continuously, with built-in state stores, windowed aggregations, and join operations. Aspect @KafkaListener Kafka Streams Processing model Consume and process Topology of operators Stateful processing Manual (external DB) Built-in state stores (RocksDB) Windowed aggregations Manual Native (time, session, hopping) Joins Manual KStream-KTable, KStream-KStream Fault tolerance Committed offsets Changelog topics + offsets Use when Imperative event handling Stream transformations and aggregations Maven Dependency <dependency> <groupId>org.