Flutter Firebase

You are a Flutter developer. The user wants to integrate Firebase services (Authentication, Firestore database, and Cloud Storage) into a Flutter application.

What to check first

• Run flutter doctor to verify Flutter SDK and Android/iOS setup are complete
• Check pubspec.yaml to see if firebase_core, firebase_auth, cloud_firestore, and firebase_storage packages are already listed
• Verify you have a Firebase project created in the Firebase Console with Android and iOS apps registered

Steps

1. Add Firebase packages to pubspec.yaml: firebase_core, firebase_auth, cloud_firestore, firebase_storage, and provider for state management
2. Run flutter pub get to download dependencies
3. Initialize Firebase in main.dart using Firebase.initializeApp() before running the app
4. Create an AuthService class to handle FirebaseAuth sign-up, login, logout, and password reset methods
5. Create a FirestoreService class to implement CRUD operations (create, read, update, delete) on Firestore collections
6. Create a StorageService class to upload files to Firebase Storage and retrieve download URLs
7. Wrap your app with ChangeNotifierProvider for state management of auth and data streams
8. Use StreamBuilder widgets to listen to real-time Firestore and authentication state changes

Code

import 'package:firebase_core/firebase_core.dart';
import 'package:firebase_auth/firebase_auth.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:firebase_storage/firebase_storage.dart';
import 'package:provider/provider.dart';
import 'package:flutter/material.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp();
  runApp(MyApp());
}

class AuthService with ChangeNotifier {
  final FirebaseAuth _auth = FirebaseAuth.instance;

  Stream<User?> get authStateChanges => _auth.authStateChanges();

  Future<UserCredential> signup(String email, String password) async {
    return await _auth.createUserWithEmailAndPassword(
      email: email,
      password: password,
    );
  }

  Future<UserCredential> login(String email, String password) async {
    return await _auth.signInWithEmailAndPassword(
      email: email,
      password: password,
    );
  }

  Future<void> logout() async {
    await _auth.signOut();
  }
}

class FirestoreService {
  final FirebaseFirestore _db = FirebaseFirestore.instance;

  Future<void> addUser(String uid, String name, String email) async {
    await _db.collection('users').doc(uid).set({

Note: this example was truncated in the source. See the GitHub repo for the latest full version.

Common Pitfalls

• Treating this skill as a one-shot solution — most workflows need iteration and verification
• Skipping the verification steps — you don't know it worked until you measure
• Applying this skill without understanding the underlying problem — read the related docs first

When NOT to Use This Skill

• When a simpler manual approach would take less than 10 minutes
• On critical production systems without testing in staging first
• When you don't have permission or authorization to make these changes

How to Verify It Worked

• Run the verification steps documented above
• Compare the output against your expected baseline
• Check logs for any warnings or errors — silent failures are the worst kind

Production Considerations

• Test in staging before deploying to production
• Have a rollback plan — every change should be reversible
• Monitor the affected systems for at least 24 hours after the change