Web Performance Optimization

What it does

This skill helps improve website performance by implementing optimization strategies. It focuses on techniques like lazy loading, code splitting, caching, compression, and monitoring to enhance Core Web Vitals and overall user experience. The skill provides examples of how to implement these optimizations using React, Webpack, image tags with srcset and loading="lazy", and service worker caching.

When to use it

This skill is useful in the following situations:

• When dealing with slow page load times.
• To address high Largest Contentful Paint (LCP) scores.
• For websites experiencing large bundle sizes.
• To reduce Cumulative Layout Shift (CLS).
• When optimizing mobile performance.

Key capabilities

• Lazy Loading: Deferring the loading of non-critical resources until they are needed.
• Code Splitting (React): Breaking down JavaScript bundles into smaller chunks for faster initial load times, demonstrated with React components and lazy.
• Webpack Bundle Optimization: Configuring Webpack to split code into vendor and application chunks.
• Image Optimization: Using <picture> tags with srcset attributes and the loading="lazy" attribute for efficient image delivery. Also includes using webp format.
• Service Worker Caching: Implementing caching strategies using service workers to improve offline performance and reduce server load.
• Core Web Vitals Monitoring: Tracking metrics like LCP, CLS, and INP (as of March 2024) for ongoing optimization efforts.

Example prompts

Here are some example prompts you could give an AI agent with this skill:

• "How can I implement code splitting in my React application?"
• "Show me how to optimize images using the <picture> tag."
• "Can you provide a basic service worker caching implementation?"
• "What are some strategies for reducing my website's bundle size?"

Tips & gotchas

• This skill provides code examples, so familiarity with web development concepts and tools like React and Webpack is helpful.
• The sendToAnalytics function in the Core Web Vitals Monitoring example is a placeholder; you’ll need to replace it with your actual analytics implementation.
• INP (Interaction to Next Paint) has replaced FID (First Input Delay) as of March 2024 for Core Web Vital monitoring.