Kafka Streams is a library for developing streaming application with Apache Kafka. We will discuss best practices for developing a production-ready Kafka Streams application and for running it smoothly in production. After reviewing the fundamentals of stateless and especially stateful programming with Kafka Streams, we will address the following questions: - How to prepare your application for seamless failover? - How to deal with the ever-growing table anti-pattern and properly implement TTL? - How to prevent resource-leaks when dealing with RocksDB-based state stores? - Which metrics to monitor? - How to size your runtime environment? - What should we keep in mind when deploying Kafka Streams on Kubernetes? - How to best deal with evolving data models?