name: expo-workflow description: Expert in Expo development workflows, EAS Build, EAS Update, Expo Go, dev clients, expo-cli commands, app configuration, and deployment strategies. Activates for expo, expo go, eas build, eas update, expo config, app.json, eas.json, expo dev client, expo prebuild, expo eject, over-the-air updates, expo doctor, expo install, managed workflow, bare workflow.

Expo Workflow Expert

Comprehensive expertise in Expo development workflows, EAS (Expo Application Services), and optimization strategies for rapid mobile development. Specializes in modern Expo SDK features, development builds, and deployment pipelines.

What I Know

Expo Fundamentals

Managed vs Bare Workflow

Managed workflow: Full Expo SDK, minimal native code
Bare workflow: Full native code access with Expo modules
When to use each approach
Migration strategies between workflows

Expo Go vs Development Builds

Expo Go: Quick testing, limited native modules
Dev Client: Full native module support, custom builds
When to switch from Expo Go to dev builds
Creating custom dev clients with EAS Build

Expo SDK & Modules

Core Expo modules (expo-camera, expo-location, etc.)
Third-party native module compatibility
Module installation best practices
Autolinking and manual linking

EAS Build (Cloud Builds)

Build Profiles

Development builds: Fast iteration, dev client
Preview builds: Internal testing, TestFlight/Internal Testing
Production builds: App Store/Play Store submission
Custom build profiles in eas.json

Platform-Specific Configuration

iOS credentials management
Android keystore handling
Build caching strategies
Environment variable injection

Build Optimization

Caching node_modules and gradle dependencies
Incremental builds
Build machine types (M1, Ubuntu)
Build time reduction strategies

EAS Update (OTA Updates)

Over-The-Air Updates

JavaScript bundle updates without app store submission
Update channels and branches
Rollout strategies (gradual rollout, instant rollout)
Rollback capabilities

Update Workflows

Development channel: Continuous updates
Preview channel: QA testing
Production channel: Staged rollouts
Emergency hotfix workflows

Update Best Practices

Version compatibility management
Update frequency optimization
Monitoring update adoption
Handling update failures gracefully

App Configuration

app.json / app.config.js

App metadata (name, slug, version)
Platform-specific configurations
Asset and icon configuration
Splash screen customization
Deep linking setup (scheme, associated domains)
Permissions configuration
Build-time environment variables

eas.json

Build profile configuration
Submit profile setup
Environment secrets management
Platform-specific build settings

Dynamic Configuration

Environment-specific configs (dev, staging, prod)
Feature flags integration
App variants (white-label apps)

Development Workflow

Fast Refresh & Hot Reloading

Understanding fast refresh behavior
Troubleshooting fast refresh issues
When to use full reload vs fast refresh

Debugging Tools

React DevTools integration
Remote debugging with Chrome DevTools
Flipper for advanced debugging
Network request inspection
Performance profiling

Local Development

Running on physical devices (QR code scanning)
Running on simulators/emulators
Offline development strategies
Tunnel mode vs LAN mode

Deployment & Distribution

App Store Submission

iOS: TestFlight, App Store Connect integration
Android: Internal testing, Play Store submission
EAS Submit command automation
Store metadata management

Internal Distribution

Ad-hoc iOS builds
Android APK distribution
Enterprise distribution
TestFlight external testing

CI/CD Integration

GitHub Actions with EAS Build
GitLab CI integration
Automated build triggers
Automated OTA updates on merge

When to Use This Skill

Ask me when you need help with:

Setting up Expo development workflow
Creating development builds with EAS Build
Configuring app.json or eas.json
Setting up over-the-air updates with EAS Update
Troubleshooting Expo Go limitations
Optimizing build times
Managing app credentials and secrets
Configuring deep linking and URL schemes
Setting up CI/CD pipelines for Expo apps
Deploying to App Store or Play Store
Understanding Expo SDK capabilities
Migrating from Expo Go to dev client
Handling native modules in Expo projects

Essential Expo Commands

Project Setup

# Create new Expo project
npx create-expo-app@latest MyApp

# Navigate to project
cd MyApp

# Start development server
npx expo start

# Install Expo module
npx expo install expo-camera

# Check project health
npx expo-doctor

Development

# Start with cache cleared
npx expo start -c

# Start with specific mode
npx expo start --dev-client  # Development build
npx expo start --go          # Expo Go

# Run on specific platform
npx expo run:ios
npx expo run:android

# Prebuild native projects (bare workflow)
npx expo prebuild

EAS Build

# Login to EAS
eas login

# Configure EAS
eas build:configure

# Build for all platforms
eas build --platform all

# Build development version
eas build --profile development --platform ios

# Build for production
eas build --profile production --platform all

# Check build status
eas build:list

EAS Update

# Configure EAS Update
eas update:configure

# Publish update to default channel
eas update --branch production --message "Fix critical bug"

# Publish to specific channel
eas update --channel preview --message "QA testing"

# List published updates
eas update:list

# Rollback update
eas update:rollback

EAS Submit

# Submit to App Store
eas submit --platform ios

# Submit to Play Store
eas submit --platform android

# Submit specific build
eas submit --platform ios --id <build-id>

Pro Tips & Tricks

1. Development Build Optimization

Create a reusable development build once, then use EAS Update for daily changes:

// eas.json
{
  "build": {
    "development": {
      "developmentClient": true,
      "distribution": "internal",
      "ios": {
        "simulator": true
      }
    }
  }
}

Build once:

eas build --profile development --platform all

Update JavaScript daily:

eas update --branch development --message "Daily changes"

2. Environment-Based Configuration

Use app.config.js for dynamic configuration:

// app.config.js
export default ({ config }) => {
  const isProduction = process.env.APP_ENV === 'production';

  return {
    ...config,
    name: isProduction ? 'MyApp' : 'MyApp Dev',
    slug: 'myapp',
    extra: {
      apiUrl: isProduction
        ? 'https://api.myapp.com'
        : 'https://dev-api.myapp.com',
      analyticsKey: process.env.ANALYTICS_KEY,
    },
    updates: {
      url: 'https://u.expo.dev/your-project-id'
    }
  };
};

3. Fast Credential Setup

Let EAS manage credentials automatically:

// eas.json
{
  "build": {
    "production": {
      "ios": {
        "credentialsSource": "remote"
      },
      "android": {
        "credentialsSource": "remote"
      }
    }
  }
}

4. Efficient Build Caching

Speed up builds by caching dependencies:

// eas.json
{
  "build": {
    "production": {
      "cache": {
        "key": "myapp-v1",
        "paths": ["node_modules", "ios/Pods", "android/.gradle"]
      }
    }
  }
}

5. Gradual OTA Rollout

Safely deploy updates to production:

# Start with 10% rollout
eas update --branch production --message "New feature" --rollout-percentage 10

# Monitor metrics, then increase
eas update:configure-rollout --branch production --percentage 50

# Full rollout
eas update:configure-rollout --branch production --percentage 100

6. Quick Testing on Physical Devices

For Expo Go (quick testing):

# Start dev server
npx expo start

# Scan QR code with:
# - iOS: Camera app
# - Android: Expo Go app

For dev client (full features):

# Install dev client once
eas build --profile development --platform ios

# Daily JavaScript updates via EAS Update
eas update --branch development

7. Troubleshooting Common Issues

"Unable to resolve module"

# Clear Metro cache
npx expo start -c

# Reinstall dependencies
rm -rf node_modules && npm install

"Build failed on EAS"

# Check build logs
eas build:list
eas build:view <build-id>

# Run prebuild locally to catch issues early
npx expo prebuild

"Update not appearing in app"

# Check update channel matches app's channel
eas channel:list

# Verify update was published successfully
eas update:list --branch production

# Force reload in app (shake device → reload)

8. Native Module Integration

When you need a native module not in Expo SDK:

# Install the module
npm install react-native-awesome-module

# Prebuild to generate native projects
npx expo prebuild

# Rebuild dev client with new module
eas build --profile development --platform all

# Continue using EAS Update for JS changes
eas update --branch development

Integration with SpecWeave

Increment Planning

Document Expo setup steps in spec.md
Include EAS Build/Update configuration in plan.md
Track build and deployment tasks in tasks.md

Testing Strategy

Use dev builds for feature development
Preview builds for QA testing
Production builds for stakeholder demos

Living Documentation

Document build profiles in .specweave/docs/internal/operations/
Track deployment procedures in runbooks
Maintain credential management procedures

Cost Optimization

Use EAS Update instead of rebuilding for JS-only changes
Cache dependencies to reduce build times
Monitor EAS usage in increment reports

expo-workflow