#I'm Starting to Hate useEffect in React — What Should I Use Instead?

"It's not you, it's me... actually, no wait, it's definitely you, useEffect."

Look, I need to get something off my chest. After years of writing React, I've come to a painful realization: useEffect is the JavaScript equivalent of duct tape. Sure, it works, but it's messy, unpredictable, and somehow always ends up in places it shouldn't be.

Don't get me wrong – useEffect was revolutionary when it first arrived. It unified class component lifecycle methods into a single, elegant hook. But like that ex who seemed perfect at first, the more time you spend with useEffect, the more red flags you start to notice.

Spoiler alert: There's a whole world of better alternatives out there, and I'm about to show you exactly what you've been missing.

#The useEffect Horror Stories (We've All Been There)

#1. The Dependency Array from Hell

Picture this: You're building a simple user dashboard. How hard could it be, right? Famous last words.

// Innocent looking code that will haunt your dreams
function UserDashboard({ userId, theme, preferences, notifications }) {
  const [user, setUser] = useState(null);
  const [stats, setStats] = useState({});
  const [isLoading, setIsLoading] = useState(true);

  useEffect(() => {
    const fetchData = async () => {
      setIsLoading(true);
      const userData = await api.getUser(userId);
      const userStats = await api.getUserStats(userId, {
        theme: theme.mode,
        includeNotifications: notifications.enabled,
        ...preferences
      });
      
      setUser(userData);
      setStats(userStats);
      setIsLoading(false);
    };

    fetchData();
  }, [userId, theme, preferences, notifications]); // 🔥 This is fine meme

  return isLoading ? <Spinner /> : <Dashboard user={user} stats={stats} />;
}

What's wrong here? Oh boy, where do I start:

theme, preferences, and notifications are objects that change reference on every parent render
This effect runs constantly, even when nothing meaningful changed
You're fetching user stats every time the theme changes (why?!)
The loading state flickers like a broken disco ball

I've seen developers spend entire afternoons debugging why their component re-renders 47 times per second. The culprit? A dependency array that looks innocent but behaves like a caffeinated squirrel.

#2. The Race Condition Nightmare

// The classic "I'll just add some async logic" trap
function ProductSearch() {
  const [query, setQuery] = useState('');
  const [results, setResults] = useState([]);
  const [isLoading, setIsLoading] = useState(false);

  useEffect(() => {
    if (!query) return;

    setIsLoading(true);
    
    // User types "laptop" then quickly changes to "phone"
    // Both API calls are now racing to set the results
    searchProducts(query)
      .then(products => {
        setResults(products); // Which response wins? 🤷‍♂️
        setIsLoading(false);
      })
      .catch(error => {
        console.error('Search failed:', error);
        setIsLoading(false);
      });
  }, [query]);

  return (
    <div>
      <input 
        value={query}
        onChange={e => setQuery(e.target.value)}
        placeholder="Search products..."
      />
      {isLoading && <div>Searching...</div>}
      {results.map(product => <ProductCard key={product.id} {...product} />)}
    </div>
  );
}

The plot twist: User searches for "laptop", then immediately changes to "phone". The laptop API call finishes last and overwrites the phone results. Your user is now very confused why they're seeing laptops when they searched for phones.

Classic useEffect behavior: "I'll just ignore that cleanup thing for now, what could go wrong?"

#3. The Infinite Loop Inception

// The "why is my browser crying?" scenario
function ChatRoom({ roomId }) {
  const [messages, setMessages] = useState([]);
  const [user, setUser] = useState({ name: 'Anonymous' });

  useEffect(() => {
    // Fetch messages when room changes
    fetchMessages(roomId).then(setMessages);
  }, [roomId]);

  useEffect(() => {
    // Update user's last seen timestamp
    setUser(prevUser => ({
      ...prevUser,
      lastSeen: new Date().toISOString()
    }));
  }, [messages]); // 🚨 DANGER ZONE

  useEffect(() => {
    // Send user data to analytics
    analytics.track('user_activity', user);
  }, [user]); // 🚨 ANOTHER DANGER ZONE

  // This component now updates forever
  // Your CPU: "Am I a joke to you?"
  return <div>Welcome to the infinite render loop!</div>;
}

What's happening: Every message update triggers a user update, which triggers analytics, which... well, you get the idea. Your component is now stuck in an infinite loop, and your laptop sounds like it's about to take off.

#4. The Testing Nightmare

// Good luck testing this monstrosity
function WeatherWidget({ location }) {
  const [weather, setWeather] = useState(null);
  const [forecast, setForecast] = useState([]);
  const [alerts, setAlerts] = useState([]);

  useEffect(() => {
    let mounted = true;
    
    const fetchWeatherData = async () => {
      try {
        const [currentWeather, weekForecast, weatherAlerts] = await Promise.all([
          weatherAPI.getCurrent(location),
          weatherAPI.getForecast(location, 7),
          weatherAPI.getAlerts(location)
        ]);

        if (mounted) {
          setWeather(currentWeather);
          setForecast(weekForecast);
          setAlerts(weatherAlerts);
        }
      } catch (error) {
        if (mounted) {
          // Handle error... somehow
        }
      }
    };

    fetchWeatherData();

    return () => {
      mounted = false;
    };
  }, [location]);

  // More useEffect hooks for auto-refresh, geolocation, etc.
  // Your test file: 300 lines of mocking hell
}

Testing this component requires:

Mocking 3 different API calls
Handling async state updates
Testing cleanup behavior
Mocking timers for auto-refresh
Praying to the JavaScript gods

No wonder developers avoid writing tests for useEffect-heavy components.

#The Great useEffect Intervention: Modern Alternatives That Actually Work

"Hi, my name is useEffect, and I have a problem..."

Enough with the horror stories. Let's talk solutions. The React ecosystem has evolved, and we now have specialized tools that do specific jobs way better than our jack-of-all-trades useEffect. It's like going from a Swiss Army knife to a professional toolkit – each tool has one job, and it does it exceptionally well.

#1. React Query/TanStack Query: The Data Fetching Superhero

Remember our nightmare UserDashboard? Let's see how React Query handles it like a boss:

// The same component, but with superpowers
function UserDashboard({ userId, theme, preferences, notifications }) {
  // Fetch user data with automatic caching and error handling
  const { data: user, isLoading: userLoading } = useQuery({
    queryKey: ['user', userId],
    queryFn: () => api.getUser(userId),
    staleTime: 5 * 60 * 1000, // Fresh for 5 minutes
    cacheTime: 10 * 60 * 1000, // Keep in cache for 10 minutes
  });

  // Fetch stats separately - React Query handles dependencies automatically
  const { data: stats, isLoading: statsLoading } = useQuery({
    queryKey: ['userStats', userId, theme.mode, notifications.enabled],
    queryFn: () => api.getUserStats(userId, {
      theme: theme.mode,
      includeNotifications: notifications.enabled,
      ...preferences
    }),
    enabled: !!user, // Only fetch stats after user is loaded
    staleTime: 2 * 60 * 1000,
  });

  const isLoading = userLoading || statsLoading;

  if (isLoading) return <Spinner />;
  
  return <Dashboard user={user} stats={stats} />;
}

What just happened? 🤯

Zero dependency arrays to manage
Automatic caching – same user data across components? No extra API calls
Background refetching – data stays fresh automatically
Parallel requests that are properly coordinated
Error boundaries built-in
Loading states handled elegantly

But wait, there's more! React Query also gives you:

// Optimistic updates for better UX
const updateUserMutation = useMutation({
  mutationFn: updateUser,
  onMutate: async (newUserData) => {
    // Cancel ongoing queries
    await queryClient.cancelQueries(['user', userId]);
    
    // Get current user data
    const previousUser = queryClient.getQueryData(['user', userId]);
    
    // Optimistically update cache
    queryClient.setQueryData(['user', userId], old => ({
      ...old,
      ...newUserData
    }));

    return { previousUser };
  },
  onError: (err, variables, context) => {
    // Rollback on error
    queryClient.setQueryData(['user', userId], context.previousUser);
  },
  onSettled: () => {
    // Refetch to ensure server state
    queryClient.invalidateQueries(['user', userId]);
  },
});

// Usage: instant UI updates, with automatic rollback on error
const handleUpdateProfile = (newData) => {
  updateUserMutation.mutate(newData);
};

#2. SWR: The Lightweight Champion

If React Query feels like overkill, SWR offers a more minimalist approach:

import useSWR, { mutate } from 'swr';

// The fetcher function - define once, use everywhere
const fetcher = (url) => fetch(url).then(res => res.json());

function UserProfile({ userId }) {
  const { data: user, error, isLoading } = useSWR(
    userId ? `/api/users/${userId}` : null, // Conditional fetching
    fetcher,
    {
      refreshInterval: 30000, // Auto-refresh every 30 seconds
      focusThrottleInterval: 5000, // Throttle refetch on window focus
      errorRetryCount: 3, // Retry failed requests
      dedupingInterval: 2000, // Dedupe identical requests
    }
  );

  // Global cache mutation - update user data across the entire app
  const updateUser = (newUserData) => {
    mutate(`/api/users/${userId}`, newUserData, false); // false = don't revalidate
  };

  if (error) return <ErrorMessage error={error} />;
  if (isLoading) return <SkeletonLoader />;

  return (
    <div>
      <UserCard user={user} onUpdate={updateUser} />
      <UserStats userId={userId} /> {/* This component will use cached user data */}
    </div>
  );
}

SWR's secret sauce:

Stale-while-revalidate strategy: Show cached data immediately, fetch fresh data in background
Global state management without the complexity
Automatic revalidation on window focus, network recovery, etc.
Built-in error handling and retry logic

#3. Event Handlers: The Forgotten Heroes

Here's a controversial take: 90% of useEffect hooks should actually be event handlers. Let me prove it:

// ❌ The useEffect way (reactive programming gone wrong)
function ProductSearch() {
  const [query, setQuery] = useState('');
  const [results, setResults] = useState([]);
  const [isSearching, setIsSearching] = useState(false);

  // This runs on EVERY query change, even single characters
  useEffect(() => {
    if (!query) {
      setResults([]);
      return;
    }

    setIsSearching(true);
    
    const timeoutId = setTimeout(() => {
      searchProducts(query)
        .then(setResults)
        .finally(() => setIsSearching(false));
    }, 300); // Debouncing with setTimeout chaos

    return () => clearTimeout(timeoutId);
  }, [query]);

  return (
    <div>
      <input 
        value={query}
        onChange={e => setQuery(e.target.value)}
      />
      {/* Results render */}
    </div>
  );
}

// ✅ The event handler way (intentional programming)
function ProductSearch() {
  const [query, setQuery] = useState('');
  const [results, setResults] = useState([]);
  const [isSearching, setIsSearching] = useState(false);

  // Debounced search function
  const debouncedSearch = useCallback(
    debounce(async (searchQuery) => {
      if (!searchQuery) {
        setResults([]);
        return;
      }

      setIsSearching(true);
      try {
        const products = await searchProducts(searchQuery);
        setResults(products);
      } catch (error) {
        toast.error('Search failed. Please try again.');
        setResults([]);
      } finally {
        setIsSearching(false);
      }
    }, 300),
    []
  );

  const handleSearchChange = (e) => {
    const newQuery = e.target.value;
    setQuery(newQuery);
    debouncedSearch(newQuery); // Explicit, intentional search trigger
  };

  const handleSearchSubmit = (e) => {
    e.preventDefault();
    debouncedSearch.cancel(); // Cancel debounced search
    debouncedSearch(query); // Search immediately
  };

  return (
    <form onSubmit={handleSearchSubmit}>
      <input 
        value={query}
        onChange={handleSearchChange}
        placeholder="Search products..."
      />
      <button type="submit">Search</button>
      {isSearching && <SearchSpinner />}
      <SearchResults results={results} />
    </form>
  );
}

Why event handlers win:

Explicit control over when things happen
Better UX with immediate search on Enter
Clearer debugging – you know exactly what triggered the search
Easier testing – just trigger events, no async timing issues

#4. Custom Hooks: The Abstraction Masters

When you do need useEffect-like behavior, wrap it in a custom hook with a clear, single responsibility:

// ❌ Scattered useEffect logic
function ChatRoom({ roomId }) {
  const [messages, setMessages] = useState([]);
  const [connectionStatus, setConnectionStatus] = useState('disconnected');
  const [unreadCount, setUnreadCount] = useState(0);

  // WebSocket connection effect
  useEffect(() => {
    const ws = new WebSocket(`ws://chat.api.com/rooms/${roomId}`);
    
    ws.onopen = () => setConnectionStatus('connected');
    ws.onclose = () => setConnectionStatus('disconnected');
    ws.onerror = () => setConnectionStatus('error');
    
    ws.onmessage = (event) => {
      const message = JSON.parse(event.data);
      setMessages(prev => [...prev, message]);
      setUnreadCount(prev => prev + 1);
    };

    return () => ws.close();
  }, [roomId]);

  // Document title effect
  useEffect(() => {
    document.title = unreadCount > 0 
      ? `(${unreadCount}) Chat Room` 
      : 'Chat Room';
  }, [unreadCount]);

  // Visibility effect
  useEffect(() => {
    const handleVisibilityChange = () => {
      if (!document.hidden) {
        setUnreadCount(0);
      }
    };

    document.addEventListener('visibilitychange', handleVisibilityChange);
    return () => document.removeEventListener('visibilitychange', handleVisibilityChange);
  }, []);

  // ... rest of component
}

// ✅ Clean custom hooks with single responsibilities
function useChatRoom(roomId) {
  const [messages, setMessages] = useState([]);
  const [connectionStatus, setConnectionStatus] = useState('disconnected');

  useEffect(() => {
    const ws = new WebSocket(`ws://chat.api.com/rooms/${roomId}`);
    
    ws.onopen = () => setConnectionStatus('connected');
    ws.onclose = () => setConnectionStatus('disconnected');
    ws.onerror = () => setConnectionStatus('error');
    
    ws.onmessage = (event) => {
      const message = JSON.parse(event.data);
      setMessages(prev => [...prev, message]);
    };

    return () => ws.close();
  }, [roomId]);

  const sendMessage = useCallback((content) => {
    if (connectionStatus === 'connected') {
      ws.send(JSON.stringify({ content, timestamp: Date.now() }));
    }
  }, [connectionStatus]);

  return { messages, connectionStatus, sendMessage };
}

function useUnreadCounter(messages) {
  const [unreadCount, setUnreadCount] = useState(0);

  useEffect(() => {
    setUnreadCount(prev => prev + 1);
  }, [messages.length]);

  useEffect(() => {
    const handleVisibilityChange = () => {
      if (!document.hidden) {
        setUnreadCount(0);
      }
    };

    document.addEventListener('visibilitychange', handleVisibilityChange);
    return () => document.removeEventListener('visibilitychange', handleVisibilityChange);
  }, []);

  return unreadCount;
}

function useDocumentTitle(title) {
  useEffect(() => {
    const originalTitle = document.title;
    document.title = title;
    return () => { document.title = originalTitle; };
  }, [title]);
}

// Clean component using specialized hooks
function ChatRoom({ roomId }) {
  const { messages, connectionStatus, sendMessage } = useChatRoom(roomId);
  const unreadCount = useUnreadCounter(messages);
  
  useDocumentTitle(
    unreadCount > 0 ? `(${unreadCount}) Chat Room` : 'Chat Room'
  );

  // Component focuses on rendering, not side effects
  return (
    <div>
      <ConnectionStatus status={connectionStatus} />
      <MessageList messages={messages} />
      <MessageInput onSend={sendMessage} />
    </div>
  );
}

#5. Zustand: State Management Without the Ceremony

Sometimes useEffect is just a poor attempt at global state management:

// ❌ useEffect trying to be a state manager
function UserProfile() {
  const [user, setUser] = useState(null);
  const [preferences, setPreferences] = useState({});
  const [notifications, setNotifications] = useState([]);

  // Sync user data across components... somehow
  useEffect(() => {
    const handleStorageChange = (e) => {
      if (e.key === 'user') {
        setUser(JSON.parse(e.newValue));
      }
    };
    
    window.addEventListener('storage', handleStorageChange);
    return () => window.removeEventListener('storage', handleStorageChange);
  }, []);

  // More useEffect madness for syncing state...
}

// ✅ Zustand: Global state that just works
import { create } from 'zustand';
import { subscribeWithSelector } from 'zustand/middleware';

const useUserStore = create(
  subscribeWithSelector((set, get) => ({
    user: null,
    preferences: {},
    notifications: [],
    
    // Actions
    setUser: (user) => set({ user }),
    updatePreferences: (newPrefs) => 
      set(state => ({ 
        preferences: { ...state.preferences, ...newPrefs } 
      })),
    
    addNotification: (notification) =>
      set(state => ({
        notifications: [...state.notifications, notification]
      })),
    
    clearNotifications: () => set({ notifications: [] }),
    
    // Async actions
    fetchUser: async (userId) => {
      const user = await api.getUser(userId);
      set({ user });
      return user;
    },
    
    logout: () => set({ user: null, preferences: {}, notifications: [] }),
  }))
);

// Subscribe to changes for side effects
useUserStore.subscribe(
  (state) => state.user,
  (user) => {
    if (user) {
      localStorage.setItem('user', JSON.stringify(user));
      analytics.identify(user.id, user.email);
    }
  }
);

// Usage in components - no useEffect needed!
function UserProfile() {
  const { user, preferences, updatePreferences } = useUserStore();
  
  if (!user) return <LoginPrompt />;
  
  return (
    <div>
      <Avatar src={user.avatar} />
      <UserSettings 
        preferences={preferences}
        onChange={updatePreferences}
      />
    </div>
  );
}

function NotificationCenter() {
  const { notifications, clearNotifications } = useUserStore();
  
  return (
    <div>
      {notifications.map(notification => (
        <NotificationItem key={notification.id} {...notification} />
      ))}
      <button onClick={clearNotifications}>Clear All</button>
    </div>
  );
}

#6. React Server Components: The Nuclear Option

Sometimes the best way to avoid useEffect is to not run on the client at all:

// ❌ Client-side data fetching with useEffect
function ProductPage({ productId }) {
  const [product, setProduct] = useState(null);
  const [reviews, setReviews] = useState([]);
  const [recommendations, setRecommendations] = useState([]);
  const [isLoading, setIsLoading] = useState(true);

  useEffect(() => {
    const fetchData = async () => {
      setIsLoading(true);
      try {
        const [productData, reviewsData, recsData] = await Promise.all([
          api.getProduct(productId),
          api.getReviews(productId),
          api.getRecommendations(productId)
        ]);
        
        setProduct(productData);
        setReviews(reviewsData);
        setRecommendations(recsData);
      } catch (error) {
        // Handle error...
      } finally {
        setIsLoading(false);
      }
    };

    fetchData();
  }, [productId]);

  if (isLoading) return <PageSkeleton />;
  
  return (
    <div>
      <ProductDetails product={product} />
      <ReviewSection reviews={reviews} />
      <RecommendationGrid recommendations={recommendations} />
    </div>
  );
}

// ✅ Server Component - no useEffect, no loading states, no race conditions
async function ProductPage({ productId }) {
  // All data fetching happens on the server
  const [product, reviews, recommendations] = await Promise.all([
    api.getProduct(productId),
    api.getReviews(productId),
    api.getRecommendations(productId)
  ]);

  return (
    <div>
      <ProductDetails product={product} />
      <ReviewSection reviews={reviews} />
      <RecommendationGrid recommendations={recommendations} />
    </div>
  );
}

Server Components benefits:

Zero client-side JavaScript for data fetching
No loading states needed (data is there when component renders)
Better SEO (content is server-rendered)
Faster initial page loads
Automatic code splitting by the framework

#The useEffect Hall of Fame: When It's Actually Good

Before you delete every useEffect in your codebase, let's acknowledge when it's still the right tool:

#1. DOM Manipulation and Third-Party Library Integration

// Perfect useEffect use case
function VideoPlayer({ src, autoplay }) {
  const videoRef = useRef(null);

  useEffect(() => {
    const video = videoRef.current;
    if (!video) return;

    // Initialize third-party video player
    const player = new VideoJS(video, {
      controls: true,
      autoplay,
      sources: [{ src, type: 'video/mp4' }]
    });

    // Cleanup is crucial for third-party libraries
    return () => {
      player.dispose();
    };
  }, [src, autoplay]);

  return <video ref={videoRef} className="video-player" />;
}

#2. Browser API Subscriptions

// Another legitimate useEffect use case
function useOnlineStatus() {
  const [isOnline, setIsOnline] = useState(navigator.onLine);

  useEffect(() => {
    const handleOnline = () => setIsOnline(true);
    const handleOffline = () => setIsOnline(false);

    window.addEventListener('online', handleOnline);
    window.addEventListener('offline', handleOffline);

    return () => {
      window.removeEventListener('online', handleOnline);
      window.removeEventListener('offline', handleOffline);
    };
  }, []); // Empty dependency array is perfect here

  return isOnline;
}

#3. Synchronizing with External Systems

// When you need to sync React state with external systems
function useLocalStorage(key, initialValue) {
  const [storedValue, setStoredValue] = useState(() => {
    try {
      const item = window.localStorage.getItem(key);
      return item ? JSON.parse(item) : initialValue;
    } catch (error) {
      return initialValue;
    }
  });

  const setValue = (value) => {
    try {
      setStoredValue(value);
      window.localStorage.setItem(key, JSON.stringify(value));
    } catch (error) {
      console.error('Error saving to localStorage:', error);
    }
  };

  // Sync with localStorage changes from other tabs
  useEffect(() => {
    const handleStorageChange = (e) => {
      if (e.key === key && e.newValue !== null) {
        try {
          setStoredValue(JSON.parse(e.newValue));
        } catch (error) {
          console.error('Error parsing localStorage value:', error);
        }
      }
    };

    window.addEventListener('storage', handleStorageChange);
    return () => window.removeEventListener('storage', handleStorageChange);
  }, [key]);

  return [storedValue, setValue];
}

#The Decision Tree: Choosing the Right Tool

When you're about to write useEffect, ask yourself these questions:

Am I fetching data?
├── Yes → Use React Query, SWR, or Server Components
└── No ↓

Am I responding to user interaction?
├── Yes → Use event handlers
└── No ↓

Am I managing global state?
├── Yes → Use Zustand, Redux Toolkit, or Context + useReducer
└── No ↓

Am I synchronizing with an external system?
├── Yes → useEffect is probably correct
└── No ↓

Am I doing this for side effects that don't depend on props/state?
├── Yes → Consider if this belongs in a useEffect at all
└── No ↓

You probably don't need useEffect.
Consider: event handlers, derived state, or memo.

#The Refactoring Strategy: From useEffect Hell to Heaven

Here's a systematic approach to cleaning up your useEffect-heavy codebase:

#Phase 1: Audit Your Effects

# Find all useEffect usage in your codebase
grep -r "useEffect" src/ --include="*.js" --include="*.jsx" --include="*.ts" --include="*.tsx"

# Categorize them:
# 1. Data fetching → React Query candidates
# 2. Event listeners → Maybe event handlers instead
# 3. State synchronization → Maybe derived state
# 4. External system sync → Keep as useEffect

#Phase 2: Replace Data Fetching Effects

// Before: Manual data fetching
function UserList() {
  const [users, setUsers] = useState([]);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState(null);

  useEffect(() => {
    fetchUsers()
      .then(setUsers)
      .catch(setError)
      .finally(() => setLoading(false));
  }, []);

  // ... rest of component
}

// After: React Query
function UserList() {
  const { data: users, isLoading, error } = useQuery({
    queryKey: ['users'],
    queryFn: fetchUsers,
  });

  // ... rest of component (much cleaner!)
}

#Phase 3: Convert Reactive Logic to Event-Driven

// Before: Reactive programming with useEffect
function ShoppingCart() {
  const [items, setItems] = useState([]);
  const [total, setTotal] = useState(0);
  const [discount, setDiscount] = useState(0);

  useEffect(() => {
    const newTotal = items.reduce((sum, item) => sum + item.price * item.quantity, 0);
    setTotal(newTotal);
  }, [items]);

  useEffect(() => {
    const newDiscount = total > 100 ? total * 0.1 : 0;
    setDiscount(newDiscount);
  }, [total]);

  // ... rest of component
}

// After: Derived state (no effects needed!)
function ShoppingCart() {
  const [items, setItems] = useState([]);
  
  // Derived state - calculated on every render (cheap calculation)
  const total = items.reduce((sum, item) => sum + item.price * item.quantity, 0);
  const discount = total > 100 ? total * 0.1 : 0;
  const finalTotal = total - discount;

  // ... rest of component
}

#Performance: The Real Talk

"But wait, won't all these libraries make my bundle huge?"

Let's look at the numbers:

React Query: ~40KB gzipped
SWR: ~10KB gzipped
Zustand: ~2KB gzipped

Your buggy useEffect code: Infinite KB of developer time

The real performance costs of useEffect:

Developer time debugging race conditions
User experience from loading flickers and stale data
Bundle size from polyfills and workarounds
Runtime performance from unnecessary re-renders

Modern alternatives are optimized by teams of experts and used by millions of developers. Your custom useEffect logic... probably isn't.

#Testing: The Proof Is in the Pudding

// Testing useEffect-heavy component: 😭
describe('UserProfile with useEffect', () => {
  it('should fetch and display user data', async () => {
    const mockUser = { id: 1, name: 'John' };
    const fetchUserSpy = jest.fn().mockResolvedValue(mockUser);
    
    // Mock the API
    jest.mock('../api', () => ({ fetchUser: fetchUserSpy }));
    
    render(<UserProfile userId={1} />);
    
    // Wait for loading to finish
    await waitFor(() => {
      expect(screen.queryByText('Loading...')).not.toBeInTheDocument();
    });
    
    // Test that user data is displayed
    expect(screen.getByText('John')).toBeInTheDocument();
    expect(fetchUserSpy).toHaveBeenCalledWith(1);
    
    // Test cleanup by unmounting
    cleanup();
    
    // Change userId prop and test re-fetch
    rerender(<UserProfile userId={2} />);
    
    await waitFor(() => {
      expect(fetchUserSpy).toHaveBeenCalledWith(2);
    });
  });
});

// Testing React Query component: 😍
describe('UserProfile with React Query', () => {
  it('should fetch and display user data', async () => {
    const mockUser = { id: 1, name: 'John' };
    
    // Mock the query
    const queryClient = new QueryClient();
    queryClient.setQueryData(['user', 1], mockUser);
    
    render(
      <QueryClientProvider client={queryClient}>
        <UserProfile userId={1} />
      </QueryClientProvider>
    );
    
    // Data is immediately available from cache
    expect(screen.getByText('John')).toBeInTheDocument();
  });
});

Testing wins with modern alternatives:

No async complexity in tests
Predictable data flow
Easy mocking with query clients
Faster test execution

#Conclusion: Breaking Up with useEffect (It's Not You, It's... Actually, It Is You)

Look, useEffect served us well during React's adolescence. It was the reliable friend who helped us transition from class components to hooks. But like that college roommate who never learned to do dishes, useEffect has overstayed its welcome.

The harsh truth: Most useEffect hooks are just bad architecture in disguise.

They're symptoms of deeper problems:

Trying to make client-side code do server-side work (data fetching)
Fighting React's declarative nature with imperative side effects
Poor separation of concerns (mixing data fetching, state management, and UI logic)
Over-engineering simple interactions (using effects for event handling)

#The New React Mindset

Modern React development is about choosing the right abstraction for each problem:

Data fetching? React Query or SWR will handle it better than you ever could
User interactions? Event handlers are more predictable than reactive effects
Global state? Zustand or Redux Toolkit beat useEffect synchronization every time
External system integration? This is where useEffect still shines

#Your Action Plan

Audit your codebase – count how many useEffect hooks are actually doing data fetching
Start with data fetching – replace those useEffect data fetchers with React Query
Convert reactive logic to event-driven – most user interactions should be handled directly
Extract reusable effects into custom hooks with clear, single purposes
Keep useEffect only for true side effects – DOM manipulation, subscriptions, external system sync

#The Bottom Line

useEffect isn't evil – it's just overused. Like a hammer seeing every problem as a nail, we've been using useEffect for problems that have better, more specialized solutions.

Your future self will thank you for making the switch. Your users will notice the improved performance. Your QA team will appreciate fewer bugs. And your code reviews will become conversations about features instead of debugging effect dependencies.

Now go forth and refactor – your components deserve better than useEffect soup.

P.S. If you're still not convinced, try this experiment: Build the same feature twice – once with traditional useEffect and once with React Query. Time how long each takes, count the bugs, and measure the bundle size. The results might surprise you.

P.P.S. If you're working on a legacy codebase with hundreds of useEffect hooks, don't panic. Refactor incrementally, starting with the most problematic components (usually the ones with multiple effects and complex dependency arrays). Rome wasn't built in a day, and your codebase won't be refactored in one either.

Happy coding, and may your dependency arrays always be correct! 🚀