react-native-fetch-client vs. Axios

// Axios (Manual configuration & boilerplate)
import axios from 'axios';

const api = axios.create({
  baseURL: 'https://api.example.com',
  timeout: 10000,
});

// Manual auth injection
api.interceptors.request.use(async (config) => {
  const token = await getAuthToken();
  if (token) config.headers.Authorization = `Bearer ${token}`;
  return config;
});

// Race-prone 401 refresh logic requires custom locks, queues, and retries
let isRefreshing = false;
let failedQueue: any[] = [];

api.interceptors.response.use(
  (res) => res,
  async (err) => {
    // 50+ lines of custom mutex code needed to prevent multiple refresh calls...
  }
);

// react-native-fetch-client (Zero dependencies, built-in primitives)
import { createClient } from 'react-native-fetch-client';

const api = createClient({
  baseURL: 'https://api.example.com',
  timeout: 10000,
  
  // 1. Dynamic Token Injection
  bearerToken: async () => await getAuthToken(),
  
  // 2. Built-in Single-Flight 401 Refresh Mutex (Zero Race Conditions!)
  auth: {
    refresh: async () => {
      const { newToken } = await refreshAuthSession();
      await saveAuthToken(newToken);
      return newToken;
    },
  },
  
  // 3. Built-in GET Deduplication & SWR Caching
  dedupe: true,
});

// Axios: Always throws on 4xx/5xx errors
try {
  const response = await api.get('/user/profile');
  console.log(response.data);
} catch (error) {
  if (axios.isAxiosError(error)) {
    console.error(error.response?.status, error.message);
  }
}

// react-native-fetch-client: Go/Rust-style Safe Tuples
const [data, error] = await api.safe.get('/user/profile');

if (error) {
  console.error(error.status, error.message);
  return;
}

console.log(data); // Fully typed, no try/catch wrapper needed