Lesson 15 — Code Splitting Cheat Sheet

React

In one line: lazy() + Suspense defer loading a route's code until the user actually visits it.

Key Ideas

1lazy(). const X = lazy(() => import("./X"));

2Suspense. Required wrapper, shows a fallback.

3Route-level splitting. The most common pattern.

Example

const Player = lazy(() => import("./pages/Player")); <Suspense fallback={<div>Loading...</div>}> <Routes> <Route path="/player/:id" element={<Player/>} /> </Routes> </Suspense>