React Suspense & Transitions

What you'll learn

• Why isLoading flags everywhere is a smell, and what replaces them
• How <Suspense> turns loading into a tree-level concern
• What 'suspending' actually means inside React
• How the use() hook reads a promise during render
• Why error boundaries are still class components in 2026
• How useTransition keeps the UI responsive during slow updates
• When to reach for useDeferredValue instead
• What <Suspense> does on the server, in plain English

1. 01
   Why Suspense exists

   The isLoading-everywhere problem, and what Suspense replaces.
   13 min
2. 02
   The Suspense boundary

   Fallbacks, nesting, and what suspending actually means under the hood.
   16 min
3. 03
   The use() hook

   Reading a promise during render, and the rules React imposes in return.
   16 min
4. 04
   Error boundaries

   Why this one piece of React is still a class component, and how to write one.
   15 min
5. 05
   useTransition

   Marking updates as non-urgent so the UI keeps breathing while data loads.
   15 min
6. 06
   useDeferredValue

   The consumer-side counterpart — throttling expensive renders without throttling input.
   14 min
7. 07
   Streaming on the server

   What a Suspense boundary does during SSR, and the shell-then-fill pattern.
   13 min
8. 08
   Putting it together

   A search-as-you-type page using useDeferredValue, <Suspense>, and use().
   13 min