Skill: Expo Expert (Standard 2026)

🎯 Primary Objectives

1. Modern Workflow Mastery: Utilizing

   expo-dev-client

   for custom native code without leaving the Expo ecosystem.
2. Native Module Engineering: Creating high-performance native bridges using the Expo Modules SDK (Swift/Kotlin).
3. EAS Orchestration: Managing CI/CD pipelines with EAS Build, Submit, and Update (OTA).
4. Local Intelligence: Implementing persistent storage with Expo SQLite and native file system management.

🏗️ The 2026 Expo Toolbelt

1. Core Services

• Expo SDK 55: Requiring the React Native New Architecture.
• Expo Router 4+: File-based routing with static typing and automatic deep linking.
• EAS Build: Cloud-based binary generation for iOS and Android.

2. Specialized SDKs

• Expo Modules SDK: The standard for writing modern native modules.
• Expo Image: High-fidelity image loading with blurhash support.
• Expo SQLite: Local database with full

  localStorage

  API support.

🛠️ Implementation Patterns

1. The Expo Module (Swift/Kotlin)

// ios/MyModule.swift
import ExpoModulesCore

public class MyModule: Module {
  public function definition() -> ModuleDefinition {
    Name("MyModule")
    Function("hello") { (name: String) -> String in
      return "Hello \(name) from Native!"
    }
  }
}

2. Expo Router (File-based Navigation)

// app/user/[id].tsx
import { useLocalSearchParams } from 'expo-router';

export default function UserPage() {
  const { id } = useLocalSearchParams();
  return <Text>User ID: {id}</Text>;
}

3. EAS Update (OTA)

eas update --branch production --message "Fix: Hydration error in Checkout"

🚫 The "Do Not List" (Anti-Patterns)

1. NEVER "Eject" (npx expo prebuild is fine, but don't commit the

   ios/android

   folders unless strictly necessary).
2. NEVER use

   react-native-navigation

   if

   Expo Router

   fits the use case.
3. NEVER store large blobs in

   AsyncStorage

   . Use

   Expo SQLite

   or the

   File System

   .
4. NEVER perform heavy work in the

   app.json

   config. Use Config Plugins for complex native modifications.

🛠️ Troubleshooting & Infrastructure

eas build --profile development

plugins

app.json

npx expo prebuild

expo-updates

expo-system-ui

📚 Reference Library

• Modern Expo Workflow: Development builds and Prebuild.
• Native Modules & Plugins: Extending the SDK.
• Local Data & Persistence: SQLite and File System.

📊 Quality Metrics

• Build Success Rate: > 95% on EAS.
• OTA Success Rate: > 99%.
• Native Crash Rate: < 0.1%.

🔄 Evolution from SDK 48 to 55

• SDK 50: Introduction of Dev Client by default.
• SDK 52: Expo Router becomes the standard.
• SDK 54: Precompiled RN for iOS, "Liquid Glass" support.
• SDK 55: Mandatory New Architecture, Predictive Back Gesture.