Explore functional reactive programming (FRP) principles applied to modern UI toolkits in this 46-minute conference talk from Strange Loop. Dive into a case study of GitHub for Mac/Windows and their FRP libraries, ReactiveCocoa and ReactiveUI. Learn about successful implementations, challenges faced, and techniques for applying FRP concepts to languages and frameworks not originally designed with FRP in mind. Discover topics such as Observables, Reactive Extensions, Commands, Observable Collections, Behaviors, and ReactiveWriting Operations. Gain insights into debugging memory leaks, virtualizing lists, and improving performance. Explore tools for logging, concurrency visualization, and DTrace integration. Understand the shift from imperative to functional programming mindsets in UI development.