Typesafe did a survey of Spark usage last year and found that a large percentage of Spark users combine it with Cassandra and Kafka. This talk focuses on streaming data scenarios that demonstrate how these three tools complement each other for building robust, scalable, and flexible data applications. Cassandra provides resilient and scalable storage, with flexible data format and query options. Kafka provides durable, scalable collection of streaming data with message-queue semantics. Spark provides very flexible analytics, everything from classic SQL queries to machine learning and graph algorithms, running in a streaming model based on "mini-batches", offline batch jobs, or interactive queries. We'll consider best practices and areas where improvements are needed.