In this talk, we will design the backend and data layer for a typical data-rich example of a social platform feed for an authenticated user. We will start with UI wireframes and move on to logical and physical Cassandra data models and query patterns. Using reactive programming paradigms, we will then optimise the process flow to perform queries efficiently in parallel. Reactive programming can look intimidating, but it doesn't have to. It's productive, elegant and fun once you get used to it! We'll look at a coding example written in Kotlin, implemented with Quarkus and Mutiny. This talk intends to give new ideas and inspiration for what’s possible with a modern, tailored, efficiently utilised stack. Prior knowledge of CQL, data partitioning/sharding concepts, and reactive programming is beneficial but optional.