react-performance SKILL.md skillA
react-performance from leahycc/claude-skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add leahycc/claude-skills/react-performance@git:20261102.80f14b4Pins git:20261102.80f14b4 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- leahycc/claude-skills
- Path
skills/react-performance/SKILL.md- Versions recorded
- 6
- Latest version
- git:20261102.80f14b4, committed Nov 2, 2026
- First version recorded
- Mar 23, 2026
- Size
- 8,886 bytes
- Repository stars
- 3
- License
- MIT
Use when optimizing React component rendering, fixing Core Web Vitals (LCP, INP, CLS), reducing bundle size, diagnosing re-renders, a store update under a large tree, code splitting, memoization decisions, Server Component patterns, or profiling React apps. Covers React 19, React Compiler, useTransition, useDeferredValue, useEffectEvent, Activity, Suspense, hydration mismatches, and Next.js optimization.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# React Performance
Comprehensive React performance guidance covering measurement, rendering optimization, bundle size, Core Web Vitals, and Server Component patterns. Verified against React docs and Web Vitals specifications.
**First principle: Measure before you optimize.** This skill teaches you to find problems before fixing them.
## Contents
- Architecture Overview
- Quick Reference
- Decision Matrix: Which Optimization?
- Choose a proportional fix
- Anti-Patterns Checklist
## Architecture Overview
```
[Diagnose]
├── React DevTools Profiler (component render times)
├── Chrome Performance Panel (main thread activity)
├── web-vitals library (LCP, INP, CLS in production)
└── Bundle analyzer (what's in the bundle)
↓
[Identify Root Cause]
├── Unnecessary re-renders? → Memoization / state colocation
├── Slow initial load? → Code splitting / Server Components
├── Janky interactions? → useTransition / useDeferredValue
├── Layout shifts? → Image/font optimization
└── Large bundle? → Dynamic imports / tree shaking
↓
[Fix — Least Invasive First]
├── 1. Restructure components (children pattern, local state)
…Read the whole file at its exact version.
How to install
mdr add leahycc/claude-skills/react-performance@sha256:d4c8080555149f9fThe line at the top of this page pins the label git:20261102.80f14b4, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_wr25yvzlnl2jyiel)
2 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 6 versions of this file, between Mar 23, 2026 and Nov 2, 2026, about one every 45 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20261102.80f14b4 latest | 2026-11-02 | 80f14b4 | 8,886 B | A | view · diff |
| git:20261024.af7209a | 2026-10-24 | af7209a | 7,503 B | A | view · diff |
| git:20261023.9ecc8c1 | 2026-10-23 | 9ecc8c1 | 7,275 B | A | view · diff |
| git:20261022.979456f | 2026-10-22 | 979456f | 7,590 B | A | view · diff |
| git:20261021.7a55aa2 | 2026-10-21 | 7a55aa2 | 7,915 B | A | view · diff |
| git:20260323.25860a6 | 2026-03-23 | 25860a6 | 7,895 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (8886 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
leahycc/claude-skills · 3 stars · license MIT · pushed 2026-11-02 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_wr25yvzlnl2jyiel GET https://markdownregistry.com/api/v1/resolve?ref=leahycc/claude-skills/react-performance GET https://markdownregistry.com/api/v1/blob/d4c8080555149f9f753fbf0b0325d25f58203bd6be3e668f42e97bc7c031f858
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.