Let's Build Suspense 🥁

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As the pendulum of web development swings back towards the server, streaming has become increasingly popular. Specifically, out-of-order streaming through features like React Suspense, the magical powers behind Server Components.

Let's build our very own simplified version to explore how it works, what problems we are trying to solve, and what this future of web development looks like.

This talk has been presented at React Summit US 2024, check out the latest edition of this React Conference.

FAQ

Suspense helps improve server-side rendering by allowing the use of streaming and out-of-order streaming, which enhances user experience by rendering components as they become available, rather than waiting for all data to load first.

Server components in React allow developers to specify which components are static and can be rendered once, and which components are dynamic and need client-side rendering and hydration, thus reducing JavaScript bundle size and improving performance.

Streaming allows the server to start sending parts of the response as they become available, rather than waiting for the entire response to be ready, thus improving the speed and user experience of web applications.

The main advantage is the reduction in JavaScript bundle size and the improvement in hydration performance, as Suspense allows components to render immediately once ready, without waiting for all components to load.

Suspense can handle asynchronous data fetching by allowing components to specify fallbacks, which are rendered while the asynchronous data is being fetched, improving the user experience by displaying loading states.

JavaScript is used to swap out loading states for actual content once it is available, employing techniques like custom elements to effectively manage the DOM elements.

By using the platform's native functionalities, server components and Suspense allow for effective caching of streamed content, enabling quick back and forth navigation in the browser history without re-fetching data from the server.

You can find more resources on Suspense, server components, and related topics through various recommended readings and links provided in the presentation, including code examples and slides.

Suspense on the server is considered impressive because it is crucial for React server components, enabling them to function effectively by managing asynchronous tasks.

Suspense allows you to render boundaries within your application to render fallback UIs like loading states whenever anything underneath those boundaries is still waiting for promises to resolve.

Julian Burr
Julian Burr
20 min
22 Nov, 2024

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Video Summary and Transcription
Hi, my name is Julian and I am super excited to be speaking at React Summit this year. Today, I will be talking about Suspense on the server and its importance in React server components. React server components allow us to differentiate between static and dynamic components, improving performance and user experience. Suspense improves performance by introducing streaming and out-of-order streaming. We can implement suspense on the server by creating a suspended object to store the suspended children and swapping out the loading state for the actual content using custom elements. Multiple suspense boundaries can be used to render individual loading states for different sections, improving the user experience.
Available in Español: Construyamos Suspense 🥁
Video transcription and chapters available for users with access.

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