Deep expertise in multiple areas of backend engineering such as data modeling, db performance tuning, state management, API design, transactionality, concurrency, memory management, fault tolerance, and scaling, with the ability to pick up new technologies quickly. That means you'd be tackling a wide array of challenges that would include optimization of our existing data model, streamlining of our asynchronous operations patterns, profiling and rightsizing our infrastructure, and developing both the tools and observability to run experiments and empirically validate results.