Skill / Fix Web Quality Skills (Addy Osmani)

Optimize web performance for faster loading and better user experience

Optimize web performance for faster loading and better user experience. Use when asked to "speed up my site", "optimize performance", "reduce load time", "fix slow loading", "improve page speed", or "performance audit".

# Performance optimization

Deep performance optimization based on Lighthouse performance audits. Focuses on loading speed, runtime efficiency, and resource optimization.

## How it works

1. Identify performance bottlenecks in code and assets
2. Prioritize by impact on Core Web Vitals
3. Provide specific optimizations with code examples
4. Measure improvement with before/after metrics

## Performance budget

| Resource | Budget | Rationale |
|----------|--------|-----------|
| Total page weight | < 1.5 MB | 3G loads in ~4s |
| JavaScript (compressed) | < 300 KB | Parsing + execution time |
| CSS (compressed) | < 100 KB | Render blocking |
| Images (above-fold) | < 500 KB | LCP impact |
| Fonts | < 100 KB | FOIT/FOUT prevention |
| Third-party | < 200 KB | Uncontrolled latency |

## Critical rendering path

### Server response

Classification

Skill Capability with explicit trigger pattern

Skill Fix

Correct or validate

Scope Project

This codebase

Triggered Activates on context match -- file patterns, topics, working state

Optimize web performance for faster loading and better user experience

Tags

Classification