---
name: next-js-optimization-bf8484c78201
description: Image, Font, Script, and Metadata optimization strategies.
metadata:
  labels: [nextjs, optimization, seo, performance]
  triggers:
    files: ['**/layout.tsx', '**/page.tsx']
    keywords: [next/image, next/font, metadata, generateMetadata]
---

# Optimization

## **Priority: P1 (HIGH)**

Core optimization primitives provided by Next.js. **Monitor First, Optimize Later.**

## Monitoring (Core Web Vitals)

Before applying optimizations, identify bottlenecks using:

- **LCP (Largest Contentful Paint)**: Initial load speed. Target < 2.5s.
- **CLS (Cumulative Layout Shift)**: Visual stability. Target < 0.1.
- **INP (Interaction to Next Paint)**: Responsiveness. Target < 200ms.
- **Tools**: Chrome DevTools "Performance" tab, `next/speed-insights`, or `React Profiler`.

## Images (`next/image`)

- **Component**: `<Image src="..." alt="..." width={500} height={300} />`.
- **Features**: Automatic resizing, lazy loading, format conversion (WebP/AVIF), and CLS prevention (placeholder sizing).
- **Remote**: Must configure `images.remotePatterns` in `next.config.js` for external URLs.

## Fonts (`next/font`)

- **Local**: `localFont({ src: ... })`.
- **Google**: `Inter({ subsets: ['latin'] })`.
- **Why**: Self-hosts fonts at build time. Zero Layout Shift.

## Metadata (SEO)

- **Static**: Export `metadata` object from `layout.tsx` or `page.tsx`.

  ```tsx
  export const metadata: Metadata = {
    title: 'Dashboard',
    description: '...',
  };
  ```

- **Dynamic**: Export `generateMetadata({ params })` function.

  ```tsx
  export async function generateMetadata({ params }) {
    const product = await getProduct(params.id);
    return { title: product.name };
  }
  ```

- **Open Graph**: Use `openGraph` key for social cards.

## Scripts (`next/script`)

- **Loading Strategy**: Control when 3rd party scripts load.
  - `strategy="afterInteractive"` (Default): Google Analytics.
  - `strategy="lazyOnload"`: Chat widgets, low priority.


---
Source attribution: ngxtm
Original project: https://github.com/ngxtm/devkit/blob/9439f27ce3fa7fe53ff9278a1ee9a44bffa70eba/rules/nextjs/optimization/SKILL.md
License: MIT
License information: https://opensource.org/license/mit
Original upstream instructions; downloaded from Mega AI Hub.

## Upstream license notice

MIT License

Copyright (c) 2024

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.



# Mega AI Hub resource metadata

Creator / publisher: ngxtm
Original project: https://github.com/ngxtm/devkit/blob/9439f27ce3fa7fe53ff9278a1ee9a44bffa70eba/rules/nextjs/optimization/SKILL.md
Attribution basis: Source repository record

Fields of work: Development & Engineering, Marketing
Roles: Frontend Developer, Growth Marketer, SEO Specialist
Specialties: API, Cross Platform, Frontend
Tools: Tool not specified
Country applicability: Country not specified
Classification basis: Source catalog labels
Instruction SHA-256: 46ada0e6093caeec65082c49a5dedbd46e9cf7cba6c9a47b8b4cd5d5ae439c96