Stream processing allows analyzing streaming data in real-time using tools like KSQL. KSQL builds on Kafka Streams to provide a SQL-like interface for transforming, filtering, and creating derived streams from immutable event data ingested into Kafka. Jupiter, a digital banking platform, uses KSQL to reconcile transactions from different interfaces in real-time and check rewards eligibility by analyzing consolidated transaction streams. While powerful, KSQL deployments require monitoring, richer SQL support, and integration with big data platforms for long-term storage.