Kappa architecture

Kappa architecture is a data architecture pattern that leverages a stream processing engine as the single source of truth for both batch and streaming data processing. It intends to eliminate the need for separate batch and stream processing systems by providing a more scalable and flexible way to process and analyze data in real-time.
It was created as a simpler alternative to the Lambda architecture as it relies on a single (streaming) engine. Kappa architecture faces challenges with late-arriving or out-of-order data, limited support for batch processing, and increased complexity in testing due to the reliance on stream processing as the single source of truth.