React Native

Build cross-platform mobile applications with React Native and TypeScript that integrate seamlessly with your Mizu backend. The React Native template provides a complete project with Expo, navigation, and state management.

Quick Start

mizu new ./my-rn-app --template mobile/reactnative

This creates a complete React Native project with:

TypeScript
Expo managed workflow
React Navigation
Zustand for state management
Axios for networking

Project Structure

my-rn-app/
├── backend/                    # Mizu Go backend
│   ├── cmd/server/
│   ├── app/server/
│   └── Makefile
│
├── app/                        # React Native app
│   ├── src/
│   │   ├── App.tsx
│   │   ├── api/
│   │   │   ├── client.ts
│   │   │   ├── endpoints.ts
│   │   │   └── types.ts
│   │   ├── components/
│   │   ├── hooks/
│   │   ├── navigation/
│   │   ├── screens/
│   │   ├── stores/
│   │   └── utils/
│   ├── app.json
│   ├── package.json
│   └── tsconfig.json
│
└── Makefile

Template Options

mizu new ./my-app --template mobile/reactnative \
  --var name=MyApp \
  --var bundleId=com.example.app \
  --var platforms=ios,android \
  --var expo=true

Variable	Description	Default
`name`	Project name	Directory name
`bundleId`	Bundle identifier	`com.example.app`
`platforms`	Target platforms	`ios,android`
`expo`	Use Expo managed workflow	`true`

API Client

// src/api/client.ts
import axios, { AxiosInstance, InternalAxiosRequestConfig } from 'axios';
import DeviceInfo from 'react-native-device-info';
import { Platform } from 'react-native';
import { useAuthStore } from '../stores/authStore';

const API_URL = process.env.EXPO_PUBLIC_API_URL ?? 'http://localhost:3000';

class ApiClient {
  private client: AxiosInstance;
  private deviceId: string | null = null;

  constructor() {
    this.client = axios.create({
      baseURL: API_URL,
      timeout: 30000,
      headers: {
        'Content-Type': 'application/json',
      },
    });

    this.setupInterceptors();
  }

  private async setupInterceptors() {
    // Request interceptor
    this.client.interceptors.request.use(
      async (config: InternalAxiosRequestConfig) => {
        // Add Mizu headers
        await this.addMizuHeaders(config);

        // Add auth token
        const token = useAuthStore.getState().accessToken;
        if (token) {
          config.headers.Authorization = `Bearer ${token}`;
        }

        return config;
      }
    );

    // Response interceptor
    this.client.interceptors.response.use(
      (response) => {
        // Check for deprecation warning
        if (response.headers['x-api-deprecated'] === 'true') {
          console.warn('API version is deprecated');
        }
        return response;
      },
      (error) => {
        if (error.response?.status === 401) {
          useAuthStore.getState().logout();
        }
        return Promise.reject(error);
      }
    );
  }

  private async addMizuHeaders(config: InternalAxiosRequestConfig) {
    if (!this.deviceId) {
      this.deviceId = await DeviceInfo.getUniqueId();
    }

    config.headers['X-Device-ID'] = this.deviceId;
    config.headers['X-App-Version'] = DeviceInfo.getVersion();
    config.headers['X-App-Build'] = DeviceInfo.getBuildNumber();
    config.headers['X-Device-Model'] = DeviceInfo.getModel();
    config.headers['X-Platform'] = Platform.OS;
    config.headers['X-OS-Version'] = Platform.Version.toString();
    config.headers['X-Timezone'] = Intl.DateTimeFormat().resolvedOptions().timeZone;
    config.headers['X-API-Version'] = 'v2';
  }

  get = <T>(url: string, params?: object) =>
    this.client.get<T>(url, { params });

  post = <T>(url: string, data?: object) =>
    this.client.post<T>(url, data);

  put = <T>(url: string, data?: object) =>
    this.client.put<T>(url, data);

  delete = <T>(url: string) =>
    this.client.delete<T>(url);
}

export const api = new ApiClient();

State Management with Zustand

Auth Store

// src/stores/authStore.ts
import { create } from 'zustand';
import { persist, createJSONStorage } from 'zustand/middleware';
import AsyncStorage from '@react-native-async-storage/async-storage';
import { api } from '../api/client';

interface User {
  id: string;
  email: string;
  name: string;
}

interface AuthState {
  user: User | null;
  accessToken: string | null;
  refreshToken: string | null;
  isAuthenticated: boolean;

  login: (email: string, password: string) => Promise<void>;
  logout: () => void;
  refreshAuth: () => Promise<void>;
}

export const useAuthStore = create<AuthState>()(
  persist(
    (set, get) => ({
      user: null,
      accessToken: null,
      refreshToken: null,
      isAuthenticated: false,

      login: async (email: string, password: string) => {
        const { data } = await api.post<{
          user: User;
          access_token: string;
          refresh_token: string;
        }>('/api/auth/login', { email, password });

        set({
          user: data.user,
          accessToken: data.access_token,
          refreshToken: data.refresh_token,
          isAuthenticated: true,
        });
      },

      logout: () => {
        set({
          user: null,
          accessToken: null,
          refreshToken: null,
          isAuthenticated: false,
        });
      },

      refreshAuth: async () => {
        const { refreshToken } = get();
        if (!refreshToken) throw new Error('No refresh token');

        const { data } = await api.post<{
          access_token: string;
        }>('/api/auth/refresh', { token: refreshToken });

        set({ accessToken: data.access_token });
      },
    }),
    {
      name: 'auth-storage',
      storage: createJSONStorage(() => AsyncStorage),
      partialize: (state) => ({
        user: state.user,
        accessToken: state.accessToken,
        refreshToken: state.refreshToken,
        isAuthenticated: state.isAuthenticated,
      }),
    }
  )
);

Items Store

// src/stores/itemsStore.ts
import { create } from 'zustand';
import { api } from '../api/client';

interface Item {
  id: string;
  name: string;
  description: string;
}

interface ItemsState {
  items: Item[];
  isLoading: boolean;
  error: string | null;

  fetchItems: () => Promise<void>;
  addItem: (item: Omit<Item, 'id'>) => Promise<void>;
  removeItem: (id: string) => Promise<void>;
}

export const useItemsStore = create<ItemsState>()((set, get) => ({
  items: [],
  isLoading: false,
  error: null,

  fetchItems: async () => {
    set({ isLoading: true, error: null });

    try {
      const { data } = await api.get<{ data: Item[] }>('/api/items');
      set({ items: data.data, isLoading: false });
    } catch (error) {
      set({ error: 'Failed to fetch items', isLoading: false });
    }
  },

  addItem: async (item) => {
    const { data } = await api.post<Item>('/api/items', item);
    set({ items: [...get().items, data] });
  },

  removeItem: async (id) => {
    await api.delete(`/api/items/${id}`);
    set({ items: get().items.filter((i) => i.id !== id) });
  },
}));

// src/navigation/RootNavigator.tsx
import { NavigationContainer } from '@react-navigation/native';
import { createNativeStackNavigator } from '@react-navigation/native-stack';
import { createBottomTabNavigator } from '@react-navigation/bottom-tabs';
import { useAuthStore } from '../stores/authStore';

// Screens
import { LoginScreen } from '../screens/LoginScreen';
import { HomeScreen } from '../screens/HomeScreen';
import { ProfileScreen } from '../screens/ProfileScreen';
import { ItemDetailScreen } from '../screens/ItemDetailScreen';

const Stack = createNativeStackNavigator();
const Tab = createBottomTabNavigator();

function MainTabs() {
  return (
    <Tab.Navigator>
      <Tab.Screen name="Home" component={HomeScreen} />
      <Tab.Screen name="Profile" component={ProfileScreen} />
    </Tab.Navigator>
  );
}

export function RootNavigator() {
  const isAuthenticated = useAuthStore((s) => s.isAuthenticated);

  return (
    <NavigationContainer>
      <Stack.Navigator screenOptions={{ headerShown: false }}>
        {isAuthenticated ? (
          <>
            <Stack.Screen name="Main" component={MainTabs} />
            <Stack.Screen
              name="ItemDetail"
              component={ItemDetailScreen}
              options={{ headerShown: true }}
            />
          </>
        ) : (
          <Stack.Screen name="Login" component={LoginScreen} />
        )}
      </Stack.Navigator>
    </NavigationContainer>
  );
}

Screens

// src/screens/HomeScreen.tsx
import React, { useEffect } from 'react';
import {
  View,
  FlatList,
  Text,
  TouchableOpacity,
  RefreshControl,
  StyleSheet,
} from 'react-native';
import { useNavigation } from '@react-navigation/native';
import { useItemsStore } from '../stores/itemsStore';

export function HomeScreen() {
  const navigation = useNavigation();
  const { items, isLoading, error, fetchItems } = useItemsStore();

  useEffect(() => {
    fetchItems();
  }, []);

  if (error) {
    return (
      <View style={styles.center}>
        <Text style={styles.error}>{error}</Text>
        <TouchableOpacity onPress={fetchItems}>
          <Text style={styles.retry}>Retry</Text>
        </TouchableOpacity>
      </View>
    );
  }

  return (
    <FlatList
      data={items}
      keyExtractor={(item) => item.id}
      refreshControl={
        <RefreshControl refreshing={isLoading} onRefresh={fetchItems} />
      }
      renderItem={({ item }) => (
        <TouchableOpacity
          style={styles.item}
          onPress={() => navigation.navigate('ItemDetail', { id: item.id })}
        >
          <Text style={styles.itemTitle}>{item.name}</Text>
          <Text style={styles.itemDescription}>{item.description}</Text>
        </TouchableOpacity>
      )}
      ListEmptyComponent={
        !isLoading ? (
          <View style={styles.center}>
            <Text>No items found</Text>
          </View>
        ) : null
      }
    />
  );
}

const styles = StyleSheet.create({
  center: { flex: 1, justifyContent: 'center', alignItems: 'center' },
  error: { color: 'red', marginBottom: 16 },
  retry: { color: 'blue' },
  item: { padding: 16, borderBottomWidth: 1, borderBottomColor: '#eee' },
  itemTitle: { fontSize: 18, fontWeight: '600' },
  itemDescription: { color: '#666', marginTop: 4 },
});

Push Notifications

// src/services/pushService.ts
import messaging from '@react-native-firebase/messaging';
import { api } from '../api/client';
import { Platform } from 'react-native';

export async function initializePushNotifications() {
  // Request permission
  const authStatus = await messaging().requestPermission();
  const enabled =
    authStatus === messaging.AuthorizationStatus.AUTHORIZED ||
    authStatus === messaging.AuthorizationStatus.PROVISIONAL;

  if (!enabled) {
    console.log('Push notifications not authorized');
    return;
  }

  // Get token
  const token = await messaging().getToken();
  await registerToken(token);

  // Listen for token refresh
  messaging().onTokenRefresh(registerToken);

  // Handle foreground messages
  messaging().onMessage(async (remoteMessage) => {
    console.log('Foreground message:', remoteMessage);
    // Show local notification
  });

  // Handle background messages
  messaging().setBackgroundMessageHandler(async (remoteMessage) => {
    console.log('Background message:', remoteMessage);
  });
}

async function registerToken(token: string) {
  try {
    await api.post('/api/push/register', {
      token,
      provider: Platform.OS === 'ios' ? 'apns' : 'fcm',
    });
  } catch (error) {
    console.error('Failed to register push token:', error);
  }
}

Deep Links

// src/services/deepLinkService.ts
import { Linking } from 'react-native';
import { NavigationContainerRef } from '@react-navigation/native';

let navigationRef: NavigationContainerRef<any> | null = null;

export function setNavigationRef(ref: NavigationContainerRef<any>) {
  navigationRef = ref;
}

export async function initializeDeepLinks() {
  // Handle initial URL
  const initialUrl = await Linking.getInitialURL();
  if (initialUrl) {
    handleDeepLink(initialUrl);
  }

  // Listen for incoming URLs
  Linking.addEventListener('url', ({ url }) => {
    handleDeepLink(url);
  });
}

function handleDeepLink(url: string) {
  if (!navigationRef) return;

  const parsed = new URL(url);
  const path = parsed.pathname;

  if (path.startsWith('/share/')) {
    const id = path.replace('/share/', '');
    navigationRef.navigate('ItemDetail', { id });
  } else if (path.startsWith('/profile/')) {
    navigationRef.navigate('Profile');
  }
}

Offline Sync

// src/services/syncService.ts
import AsyncStorage from '@react-native-async-storage/async-storage';
import { api } from '../api/client';

const SYNC_TOKEN_KEY = 'sync_token';

export async function sync() {
  const syncToken = await AsyncStorage.getItem(SYNC_TOKEN_KEY);

  const params: Record<string, string> = {};
  if (syncToken) {
    params.sync_token = syncToken;
  }

  const { data } = await api.get<SyncResponse>('/api/sync', params);

  // Apply changes to local storage
  await applyChanges(data);

  // Save new sync token
  await AsyncStorage.setItem(SYNC_TOKEN_KEY, data.sync_token);
}

async function applyChanges(response: SyncResponse) {
  // Get current items
  const itemsJson = await AsyncStorage.getItem('items');
  const items: Map<string, Item> = new Map(
    itemsJson ? JSON.parse(itemsJson) : []
  );

  // Apply created
  for (const item of response.created) {
    items.set(item.id, item);
  }

  // Apply updated
  for (const item of response.updated) {
    items.set(item.id, item);
  }

  // Apply deleted
  for (const id of response.deleted) {
    items.delete(id);
  }

  // Save back
  await AsyncStorage.setItem('items', JSON.stringify([...items]));
}

Running the Project

Start Backend

cd backend
make run

Run React Native App

cd app

# Install dependencies
npm install

# iOS
npx expo run:ios

# Android
npx expo run:android

# Development with Expo Go
npx expo start

Best Practices

Type Safety

// src/api/types.ts
export interface PageResponse<T> {
  data: T[];
  page: number;
  per_page: number;
  total: number;
  total_pages: number;
}

export interface ApiError {
  code: string;
  message: string;
  details?: Record<string, unknown>;
}

// Type-safe API calls
const response = await api.get<PageResponse<Item>>('/api/items');

Error Handling

// src/utils/errorHandler.ts
import { AxiosError } from 'axios';
import { Alert } from 'react-native';

export function handleApiError(error: unknown) {
  if (error instanceof AxiosError) {
    const apiError = error.response?.data as ApiError | undefined;

    switch (apiError?.code) {
      case 'upgrade_required':
        Alert.alert('Update Required', 'Please update the app to continue.');
        break;
      case 'maintenance':
        Alert.alert('Maintenance', apiError.message);
        break;
      default:
        Alert.alert('Error', apiError?.message ?? 'Something went wrong');
    }
  }
}

Next Steps

Flutter

Build with Flutter

Push Notifications

FCM integration

Deep Links

Universal Links

Templates

All mobile templates

Getting Started

Core Concepts

Backend Features

Native Platforms

Cross-Platform

Web & Games

Deployment

Templates

Reference

Quick Start

Project Structure

Template Options

API Client

State Management with Zustand

Auth Store

Items Store

Navigation

Screens

Push Notifications

Deep Links

Offline Sync

Running the Project

Start Backend

Run React Native App

Best Practices

Type Safety

Error Handling

Next Steps

Flutter

Push Notifications

Deep Links

Templates

Getting Started

Core Concepts

Backend Features

Native Platforms

Cross-Platform

Web & Games

Deployment

Templates

Reference

​Quick Start

​Project Structure

​Template Options

​API Client

​State Management with Zustand

​Auth Store

​Items Store

​Navigation

​Screens

​Push Notifications

​Deep Links

​Offline Sync

​Running the Project

​Start Backend

​Run React Native App

​Best Practices

​Type Safety

​Error Handling

​Next Steps

Flutter

Push Notifications

Deep Links

Templates

Quick Start

Project Structure

Template Options

API Client

State Management with Zustand

Auth Store

Items Store

Navigation

Screens

Push Notifications

Deep Links

Offline Sync

Running the Project

Start Backend

Run React Native App

Best Practices

Type Safety

Error Handling

Next Steps