Web Performance

by addyosmani

Web Performance is a Frontend skill for Claude Code, published by addyosmani in web-quality-skills.

2.6K stars239 forkson addyosmani/web-quality-skillsAdded 2026/08/18+1% in starsRepository updated 2026/06/14

View source on GitHub Download repo ZIP

accessibilityagent-skillsclaude-skillscore-web-vitalslighthouseskillstestingweb-performance

Install in seconds

Install Web Performance

Copy Web Performance into your Claude Code skills folder. Run the command in your terminal, or review the source on GitHub before installing.

terminal

npx degit https://github.com/addyosmani/web-quality-skills/tree/main/skills/performance ~/.claude/skills/performance

Requires Node.js. Downloads this skill only — not the rest of the repository — into your Claude Code skills folder.

Without Node.js

git clone https://github.com/addyosmani/web-quality-skills.git

Clones the whole repository, then copy the skill’s own directory into your skills folder yourself.

In this catalog

Source file: skills/performance/SKILL.md in addyosmani/web-quality-skills
Installs to: ~/.claude/skills/performance
Collection: One of 6 skills cataloged from this repository
Category: Frontend — 567 skills

What Web Performance does

Web Performance improves site speed by optimizing loading, runtime efficiency, and resource delivery. Use it when asked to speed up a site, reduce load time, improve page speed, or run a performance audit.

Web Performance is cataloged under Frontend on DirSkills. Web Performance comes from a repository tagged accessibility, agent-skills, claude-skills, core-web-vitals and lighthouse.

Documentation

README

Excerpt

Performance optimization

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

How it works

Identify performance bottlenecks in code and assets
Prioritize by impact on Core Web Vitals
Provide specific optimizations with code examples
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

This is the opening of the README. Read the full README on GitHub.

Frequently asked about Web Performance

What else does addyosmani publish alongside Web Performance?
Web Performance is one of 6 skills that DirSkills catalogs from addyosmani/web-quality-skills, the repository it ships in. Its siblings there include Accessibility, Core Web Vitals and SEO. Each one is a separate skill with its own page in this directory, installs the same way Web Performance does, and is maintained by addyosmani in that same repository. The rest of the collection is listed on the addyosmani/web-quality-skills page.
How does Web Performance compare to other Frontend skills?
Web Performance ranks #191 by stars among the 567 Frontend skills in this catalog. The most-starred ones next to it are Angular Developer, Android Clean Architecture and Accessibility. DirSkills ranks by the star count of the repository each skill ships in, so that order reflects how popular those repositories are rather than any review of Web Performance against them. Open each page to compare what they document and how they install.