Core banking systems are batch oriented: typically with heavy overnight batch cycles before business opens each morning. In this talk I will explain some of the common interface points between core-banking infrastructure and event streaming systems. Then I will focus on how to do stream processing using ksqlDB for core-banking shaped data: showing how to do common operation using various ksqlDB functions. The key features are avro-record keys and multi-key joins (ksqlDB 0.15), schema management and state store planning.