# SkillPatch skill: expo-dev-client

This skill guides agents through building and distributing Expo development clients using EAS Build, either locally or via TestFlight. It covers EAS configuration, platform-specific build commands, installation steps, and troubleshooting for both iOS and Android. It also helps agents determine when a dev client is actually needed versus using standard Expo Go.

You (the agent) were given this URL and asked to use this skill. This is a **public** skill — no SkillPatch account, API key, or prior setup is required. Two ways to use it:

**1. Use it right now** — the skill's complete file tree (SKILL.md + all reference files) is inlined below; read `SKILL.md` first, then follow it, consulting the other files as it directs.

**2. Install the exact package onto disk** (recommended if you can run a shell — this reproduces the skill byte-for-byte, including any binary assets that can't be inlined):

```bash
mkdir -p .claude/skills/expo-dev-client
curl -sSL https://skillpatch.dev/install_skill/expo-dev-client | tar -xz -C .claude/skills/
```

(`.claude/skills/` is Claude Code's convention; use whatever directory your agent loads skills from.)


---

## Skill files (2)

- `SKILL.md`
- `agents/openai.yaml`


### `SKILL.md`

````markdown
---
name: expo-dev-client
description: Build and distribute Expo development clients locally or via TestFlight
version: 1.0.0
license: MIT
---

Use EAS Build to create development clients for testing native code changes on physical devices. Use this for creating custom Expo Go clients for testing branches of your app.

## Important: When Development Clients Are Needed

**Only create development clients when your app requires custom native code.** Most apps work fine in Expo Go.

You need a dev client ONLY when using:
- Local Expo modules (custom native code)
- Apple targets (widgets, app clips, extensions)
- Third-party native modules not in Expo Go

**Try Expo Go first** with `npx expo start`. If everything works, you don't need a dev client.

## EAS Configuration

Ensure `eas.json` has a development profile:

```json
{
  "cli": {
    "version": ">= 16.0.1",
    "appVersionSource": "remote"
  },
  "build": {
    "production": {
      "autoIncrement": true
    },
    "development": {
      "autoIncrement": true,
      "developmentClient": true
    }
  },
  "submit": {
    "production": {},
    "development": {}
  }
}
```

Key settings:
- `developmentClient: true` - Bundles expo-dev-client for development builds
- `autoIncrement: true` - Automatically increments build numbers
- `appVersionSource: "remote"` - Uses EAS as the source of truth for version numbers

## Building for TestFlight

Build iOS dev client and submit to TestFlight in one command:

```bash
eas build -p ios --profile development --submit
```

This will:
1. Build the development client in the cloud
2. Automatically submit to App Store Connect
3. Send you an email when the build is ready in TestFlight

After receiving the TestFlight email:
1. Download the build from TestFlight on your device
2. Launch the app to see the expo-dev-client UI
3. Connect to your local Metro bundler or scan a QR code

## Building Locally

Build a development client on your machine:

```bash
# iOS (requires Xcode)
eas build -p ios --profile development --local

# Android
eas build -p android --profile development --local
```

Local builds output:
- iOS: `.ipa` file
- Android: `.apk` or `.aab` file

## Installing Local Builds

Install iOS build on simulator:

```bash
# Find the .app in the .tar.gz output
tar -xzf build-*.tar.gz
xcrun simctl install booted ./path/to/App.app
```

Install iOS build on device (requires signing):

```bash
# Use Xcode Devices window or ideviceinstaller
ideviceinstaller -i build.ipa
```

Install Android build:

```bash
adb install build.apk
```

## Building for Specific Platform

```bash
# iOS only
eas build -p ios --profile development

# Android only
eas build -p android --profile development

# Both platforms
eas build --profile development
```

## Checking Build Status

```bash
# List recent builds
eas build:list

# View build details
eas build:view
```

## Using the Dev Client

Once installed, the dev client provides:
- **Development server connection** - Enter your Metro bundler URL or scan QR
- **Build information** - View native build details
- **Launcher UI** - Switch between development servers

Connect to local development:

```bash
# Start Metro bundler
npx expo start --dev-client

# Scan QR code with dev client or enter URL manually
```

## Troubleshooting

**Build fails with signing errors:**
```bash
eas credentials
```

**Clear build cache:**
```bash
eas build -p ios --profile development --clear-cache
```

**Check EAS CLI version:**
```bash
eas --version
eas update
```

````


### `agents/openai.yaml`

```
interface:
  display_name: "Expo Dev Client"
  short_description: "Create and use Expo development clients when Expo Go is not enough"
  default_prompt: "Use $expo-dev-client to decide whether an Expo development client is required, configure development EAS profiles, build local or cloud dev clients, and connect them to Metro."

```