Next.js Tips That Actually Made My Apps Faster

I've shipped enough Next.js apps to know what actually matters. Here's my list.

1. Stop Making Everything a Client Component

Every 'use client' = more JavaScript shipped. I was putting it everywhere. Don't.

// This runs on server. Zero JS to client.
export async function ProjectList() {
  const projects = await db.projects.findMany();
  return (
    <ul>
      {projects.map(p => <li key={p.id}>{p.name}</li>)}
    </ul>
  );
}

Only add 'use client' when you actually need interactivity. useState? onClick? Fine. Otherwise, keep it server.

2. next/image Is Not Optional

I used regular <img> tags on an early project. Lighthouse score: 45. Switched to next/image. Score: 89.

<Image
  src="/hero.jpg"
  alt="Hero"
  width={1200}
  height={600}
  priority // Above the fold? Use this.
  placeholder="blur"
/>

It's not just optimization — it's free performance.

3. Dynamic Imports for Heavy Stuff

Had a chart library adding 200KB to my bundle. Users saw it on one page.

const Chart = dynamic(() => import('./HeavyChart'), {
  loading: () => <div>Loading chart...</div>,
  ssr: false,
});

Now it loads only when needed. Bundle size dropped. Users on slow connections thanked me (not literally, but spiritually).

4. Cache Like You Mean It

// Static data? Cache forever.
fetch(url, { cache: 'force-cache' })

// Changes sometimes? Revalidate.
fetch(url, { next: { revalidate: 3600 } }) // 1 hour

// Real-time? Don't cache.
fetch(url, { cache: 'no-store' })

I default to revalidate: 3600 and adjust from there.

5. Parallel Data Fetching

This is slow:

const user = await getUser();
const posts = await getPosts(); // Waits for user
const comments = await getComments(); // Waits for posts

This is fast:

const [user, posts, comments] = await Promise.all([
  getUser(),
  getPosts(),
  getComments(),
]);

If they don't depend on each other, fetch in parallel.

6. Analyze Your Bundle

npm install @next/bundle-analyzer
ANALYZE=true npm run build

Found a 150KB dependency I imported once. Removed it. Bundle shrunk. Users happy.

The Result

TaskNotch and ZyMerge both score 90+ on Lighthouse. Not because I'm smart — because I stopped making dumb mistakes.

Your move.