Mobile DevOps (EAS + Fastlane)

Expert guidance for automating mobile app builds, submissions, and over-the-air updates using EAS (Expo Application Services) and Fastlane.

Overview

Service	Purpose
EAS Build	Cloud builds for iOS and Android
EAS Submit	Automated submission to App Store / Play Store
EAS Update	Over-the-air (OTA) JavaScript updates
EAS Workflows	CI/CD pipelines with YAML configuration
Fastlane	Additional automation (screenshots, metadata, certificates)

Quick Start

1. Initialize EAS

bash

# Install EAS CLI
npm install -g eas-cli

# Login to Expo account
eas login

# Initialize EAS in your project
eas init

# Configure build profiles
eas build:configure

2. Configure eas.json

See references/eas-json.md for complete configuration.

json

{
  "cli": {
    "version": ">= 16.3.0",
    "appVersionSource": "remote"
  },
  "build": {
    "development": {
      "developmentClient": true,
      "distribution": "internal"
    },
    "preview": {
      "distribution": "internal",
      "channel": "preview"
    },
    "production": {
      "channel": "production",
      "autoIncrement": true
    }
  },
  "submit": {
    "production": {}
  }
}

3. Create Your First Workflow

Create .eas/workflows/build.yml:

yaml

name: Build Apps

on:
  push:
    branches: [main]

jobs:
  build_android:
    name: Build Android
    type: build
    params:
      platform: android
      profile: production

  build_ios:
    name: Build iOS
    type: build
    params:
      platform: ios
      profile: production

Run manually:

bash

eas workflow:run .eas/workflows/build.yml

EAS Workflows

YAML Structure

See references/eas-workflows.md for complete syntax.

yaml

name: Workflow Name

on:
  push:
    branches: [main, develop]
  pull_request:
    branches: [main]
  workflow_dispatch:
    inputs:
      environment:
        type: choice
        options: [staging, production]

jobs:
  job_id:
    name: Display Name
    type: build | submit | update | fingerprint | get-build
    needs: [other_job]
    if: ${{ condition }}
    environment: production
    params:
      platform: android | ios
      profile: production

Pre-packaged Job Types

Type	Description	Key Params
`build`	Build app binary	`platform`, `profile`
`submit`	Submit to app stores	`build_id`, `profile`
`update`	Publish OTA update	`branch`, `channel`, `platform`
`fingerprint`	Generate native fingerprint	`environment`
`get-build`	Find existing build	`fingerprint_hash`, `profile`
`maestro`	Run E2E tests	`build_id`, `flow_path`
`slack`	Send Slack notification	`webhook_url`, `message`

Production Deployment Workflow

yaml

name: Deploy to Production

on:
  push:
    branches: [main]

jobs:
  # Check if native code changed
  fingerprint:
    name: Fingerprint
    type: fingerprint
    environment: production

  # Look for existing compatible build
  get_android_build:
    name: Check Android Build
    needs: [fingerprint]
    type: get-build
    params:
      fingerprint_hash: ${{ needs.fingerprint.outputs.android_fingerprint_hash }}
      profile: production

  get_ios_build:
    name: Check iOS Build
    needs: [fingerprint]
    type: get-build
    params:
      fingerprint_hash: ${{ needs.fingerprint.outputs.ios_fingerprint_hash }}
      profile: production

  # Build only if no compatible build exists
  build_android:
    name: Build Android
    needs: [get_android_build]
    if: ${{ !needs.get_android_build.outputs.build_id }}
    type: build
    params:
      platform: android
      profile: production

  build_ios:
    name: Build iOS
    needs: [get_ios_build]
    if: ${{ !needs.get_ios_build.outputs.build_id }}
    type: build
    params:
      platform: ios
      profile: production

  # Submit new builds to stores
  submit_android:
    name: Submit to Play Store
    needs: [build_android]
    type: submit
    params:
      build_id: ${{ needs.build_android.outputs.build_id }}

  submit_ios:
    name: Submit to App Store
    needs: [build_ios]
    type: submit
    params:
      build_id: ${{ needs.build_ios.outputs.build_id }}

  # Publish OTA update if build exists
  update_android:
    name: OTA Update Android
    needs: [get_android_build]
    if: ${{ needs.get_android_build.outputs.build_id }}
    type: update
    params:
      branch: production
      platform: android

  update_ios:
    name: OTA Update iOS
    needs: [get_ios_build]
    if: ${{ needs.get_ios_build.outputs.build_id }}
    type: update
    params:
      branch: production
      platform: ios

EAS Commands Reference

Build Commands

bash

# Build for specific platform
eas build --platform ios --profile production
eas build --platform android --profile preview
eas build --platform all --profile development

# Build with auto-submit
eas build --platform ios --auto-submit

# Local build (experimental)
eas build --platform android --local

# List builds
eas build:list

# View build details
eas build:view [BUILD_ID]

# Cancel build
eas build:cancel [BUILD_ID]

Submit Commands

bash

# Submit latest build
eas submit --platform ios --latest
eas submit --platform android --latest

# Submit specific build
eas submit --platform ios --id [BUILD_ID]

# Submit local file
eas submit --platform android --path ./app.aab

Update Commands

bash

# Publish update
eas update --branch production --message "Bug fixes"

# Publish to specific channel
eas update --channel preview --message "New feature"

# List updates
eas update:list --branch production

# Rollback (republish previous update)
eas update:republish --group [UPDATE_GROUP_ID]

Workflow Commands

bash

# Run workflow
eas workflow:run .eas/workflows/deploy.yml

# Validate workflow
eas workflow:validate .eas/workflows/deploy.yml

# List workflow runs
eas workflow:runs

# View workflow logs
eas workflow:logs [WORKFLOW_ID]

# Cancel workflow
eas workflow:cancel [WORKFLOW_ID]

Channels & Branches Strategy

Recommended Setup

code

Channel          Branch          Environment
─────────────────────────────────────────────
development  →   development  →   Dev builds
preview      →   preview      →   Internal testing
staging      →   staging      →   QA / Beta
production   →   production   →   App Store / Play Store

Configuration in eas.json

json

{
  "build": {
    "development": {
      "developmentClient": true,
      "distribution": "internal",
      "channel": "development"
    },
    "preview": {
      "distribution": "internal",
      "channel": "preview"
    },
    "staging": {
      "distribution": "internal",
      "channel": "staging"
    },
    "production": {
      "channel": "production",
      "autoIncrement": true
    }
  }
}

Credentials Management

iOS Credentials

bash

# Interactive credentials setup
eas credentials --platform ios

# Credentials include:
# - Distribution Certificate
# - Provisioning Profile
# - Push Notification Key
# - App Store Connect API Key (for submit)

Android Credentials

bash

# Interactive credentials setup
eas credentials --platform android

# Credentials include:
# - Keystore (upload key or legacy app signing key)
# - Google Service Account (for submit)

Environment Variables

Build-time Secrets

bash

# Set secret
eas secret:create --name API_KEY --value "your-secret-key" --scope project

# List secrets
eas secret:list

# Delete secret
eas secret:delete API_KEY

Using in eas.json

json

{
  "build": {
    "production": {
      "env": {
        "API_URL": "https://api.production.com",
        "SENTRY_DSN": "@SENTRY_DSN"
      }
    }
  }
}

Fastlane Integration

See references/fastlane.md for Fastlane patterns.

Using Fastlane in EAS Workflows

yaml

defaults:
  tools:
    fastlane: 2.224.0

jobs:
  screenshots:
    runs_on: macos-large
    steps:
      - uses: eas/checkout
      - name: Capture Screenshots
        run: fastlane screenshots
        working_directory: ./ios

Resources

•EAS JSON Config: references/eas-json.md
•EAS Workflows Syntax: references/eas-workflows.md
•Fastlane Patterns: references/fastlane.md
•Deployment Patterns: references/deployment-patterns.md