Preload Based on User Intent

Preload heavy bundles before they're needed to reduce perceived latency.

Example (preload on hover/focus):

tsx

function EditorButton({onClick}: {onClick: () => void}) {
  const preload = () => {
    if (typeof window !== 'undefined') {
      void import('./monaco-editor')
    }
  }

  return (
    <button onMouseEnter={preload} onFocus={preload} onClick={onClick}>
      Open Editor
    </button>
  )
}

Example (preload when feature flag is enabled):

tsx

function FlagsProvider({children, flags}: Props) {
  useEffect(() => {
    if (flags.editorEnabled && typeof window !== 'undefined') {
      void import('./monaco-editor').then((mod) => mod.init())
    }
  }, [flags.editorEnabled])

  return <FlagsContext.Provider value={flags}>{children}</FlagsContext.Provider>
}

The typeof window !== 'undefined' check prevents bundling preloaded modules for SSR, optimizing server bundle size and build speed.