This talk is a deep dive on how React concurrently renders to provide time slicing and touches on concurrent hooks like useTransition and useSyncExternalStore.

React has changed a lot in the last year: React 19, 19.1 and now 19.2 brought a stable React Compiler, new hooks like useEffectEvent, the <Activity /> API, and better SSR primitives such as Partial Pre-rendering. And more

In this talk we’ll take a demo React app that’s full of effects, memoization and “old school” patterns, and modernize it step by step

React has changed a lot in the last year: React 19, 19.1 and now 19.2 brought a stable React Compiler, new hooks like useEffectEvent, the <Activity /> API, and better SSR primitives such as Partial Pre-rendering. And more

In this talk we’ll take a demo React app that’s full of effects, memoization and “old school” patterns, and modernize it step by step.

Writing fluid user interfaces becomes more and more challenging as the application complexity increases. Also, in a world with a wide variety of network connections, any user can have a slow experience, and apps that delight users on fast connections can barely be usable on slow ones. Leveraging real-world case studies from small, medium, and enterprise-scale companies, in this workshop, we will:

↝ Have an in-depth overview of the important concepts behind reconciliation and React Fiber and and go through a few magic words we hear a lot, like coroutines, generators, and more.

↝ Explore how proper scheduling can improve your app’s experience by diving into some concurrent React features, understanding their rationales, and how they work under the hood.

↝ Discuss a wide range of performance APIs native to the Web Platform itself.

↝ See how to measure responsiveness, and reliably identify culprits for bad experiences.

↝ Discuss how to apply modern techniques to legacy codebases, via code generation, polyfilling, and many other tips and tricks for large platforms targeting emerging markets.