What is react-native-expert?

A React Native and Expo development guide for building mobile apps that run on both iOS and Android.

Use it to set up navigation, build components, handle platform-specific code, optimize lists and images, and troubleshoot iOS or Android builds.

It helps organize cross-platform features, diagnose build and bundler errors, and check behavior on both mobile platforms.

react-native-expert — Skill for Claude Code and Codex by eric861129

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent

npx skills add eric861129/SKILLS_All-in-one --skill react-native-expert

Clone the repo

git clone --depth 1 https://github.com/eric861129/SKILLS_All-in-one

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/eric861129/skills_all-in-one/react-native-expert/github.svg)](https://agentmods.dev/skills/eric861129/skills_all-in-one/react-native-expert)

Your own site

<a href="https://agentmods.dev/skills/eric861129/skills_all-in-one/react-native-expert"><img src="https://agentmods.dev/badge/skills/eric861129/skills_all-in-one/react-native-expert/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/eric861129/skills_all-in-one/react-native-expert"><img src="https://agentmods.dev/badge/skills/eric861129/skills_all-in-one/react-native-expert.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 99 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 1,556 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin 95% copy Near-identical to another mod in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00099	$0.01556
Opus 5.5	$0.00040	$0.00622
Sonnet 5.5	$0.00020	$0.00311
Haiku 4.5	$0.00010	$0.00156

Measured 1mo ago against content hash 927fee5379af, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

react-native-expert scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

95% identical to react-native-expert — 5 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

public/SKILLS/Development & Code Tools/react-native-expert/SKILL.md · 186 lines

How it starts

The opening of the file, as written. The whole thing — 186 lines — stays where its author put it; the contents beside it link to each section on GitHub.

React Native Expert

Senior mobile engineer building production-ready cross-platform applications with React Native and Expo.

Core Workflow

Setup — Expo Router or React Navigation, TypeScript config → run npx expo doctor to verify environment and SDK compatibility; fix any reported issues before proceeding
Structure — Feature-based organization
Implement — Components with platform handling → verify on iOS simulator and Android emulator; check Metro bundler output for errors before moving on
Optimize — FlatList, images, memory → profile with Flipper or React DevTools
Test — Both platforms, real devices

Error Recovery

Metro bundler errors → clear cache with npx expo start --clear, then restart
iOS build fails → check Xcode logs → resolve native dependency or provisioning issue → rebuild with npx expo run:ios
Android build fails → check adb logcat or Gradle output → resolve SDK/NDK version mismatch → rebuild with npx expo run:android
Native module not found → run npx expo install <module> to ensure compatible version, then rebuild native layers

Reference Guide

Load detailed guidance based on context:

Topic	Reference	Load When
Navigation	`references/expo-router.md`	Expo Router, tabs, stacks, deep linking
Platform	`references/platform-handling.md`	iOS/Android code, SafeArea, keyboard
Lists	`references/list-optimization.md`	FlatList, performance, memo
Storage	`references/storage-hooks.md`	AsyncStorage, MMKV, persistence
Structure	`references/project-structure.md`	Project setup, architecture

Constraints

MUST DO

Use FlatList/SectionList for lists (not ScrollView)
Implement memo + useCallback for list items
Handle SafeAreaView for notches
Test on both iOS and Android real devices
Use KeyboardAvoidingView for forms
Handle Android back button in navigation

MUST NOT DO

Use ScrollView for large lists
Use inline styles extensively (creates new objects)
Hardcode dimensions (use Dimensions API or flex)
Ignore memory leaks from subscriptions
Skip platform-specific testing
Use waitFor/setTimeout for animations (use Reanimated)

Read the full file on GitHub · 186 lines

Files

What ships with it

5 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

1mo ago First seen · 186 lines · 99 tokens per session scan A 927fee5379af

Subscribe to this mod's changes

react-native-expert is a skill published in the GitHub repository eric861129/SKILLS_All-in-one (52 stars, last pushed 6mo ago), licensed MIT. It adds 99 tokens to every session and 1,556 once invoked, about $0.0004 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 95% identical to react-native-expert, differing in 5 lines, and is treated as a copy.

Claude Code Frontend Mobile React agent-workflows ai-agent ai-tools chatgpt developer-tools

react-native-expo

Build and upgrade React Native or Expo applications with navigation, native modules and verified platform integration. Use when implementing mobile screens, Expo Router flows or device capabilities; choose a supported SDK combination rather than forcing independent latest packages together.

WrongStack/WrongStack · 49 tokens

react-native-expert