3 Common Async/Await Mistakes in React

Understanding Route Handlers in Next.js (App Router) Been working with the Next.js App Router recently, and one feature I think more developers should take advantage of is Route Handlers. They let you build backend logic directly inside your /app directory using the Web Request/Response APIs — no separate API routes needed. Here’s why they’re powerful: 🔵 1. Simple, file‑based backend logic Just drop a route.ts file anywhere inside /app: export async function GET(request: Request) {} Next.js automatically maps it to an API endpoint. Clean, predictable, and colocated with your UI. 🟠 2. Full support for HTTP methods GET, POST, PUT, PATCH, DELETE, HEAD, OPTIONS — all supported out of the box. If a method isn’t implemented, Next.js returns 405 Method Not Allowed automatically 🔵 3. Extended NextRequest & NextResponse You get helpers for cookies, headers, URL parsing, redirects, and more — perfect for auth, data validation, and secure server logic. 🟠 4. Smart caching behavior GET handlers can be cached using export const dynamic = 'force-static' Other methods always run dynamically Prerendering stops when you access runtime data (headers, cookies, DB queries, etc.) 🔵 5. Great for Backend‑for‑Frontend (BFF) patterns You can fetch external APIs, sanitize responses, enforce auth, and return exactly what your React components need — all inside the same route segment. Route Handlers feel like the missing piece between frontend and backend. They keep your logic close to your UI, reduce boilerplate, and make Next.js a true full‑stack framework. #Nextjs #ReactJS #WebDevelopment #FullStackDeveloper #JavaScript #TypeScript #APIDevelopment #BackendForFrontend #WebEngineering #CodingTips

⚡ A Simple React Performance Trick: Lazy Loading Components One performance issue I’ve noticed in many React applications is large bundle sizes. When an app loads too much JavaScript upfront, it can slow down the initial page load and impact user experience. One simple solution for this is Lazy Loading. Instead of loading all components at once, we can load them only when they are needed. Here’s a simple example 👇 import React, { lazy, Suspense } from "react"; const Dashboard = lazy(() => import("./Dashboard")); function App() { return ( <Suspense fallback={Loading...}> ); } What’s happening here? 🔹 React.lazy() loads the component only when it is rendered 🔹 Suspense shows a fallback UI while the component is loading 🔹 This reduces the initial bundle size Why this matters 👇 ✅ Faster initial page load ✅ Better performance for large applications ✅ Improved user experience This technique becomes especially useful for: • Dashboards • Admin panels • Large feature modules • Route-based components 💡 One thing I’ve learned while working with React: Small performance optimizations like lazy loading and code splitting can make a big difference as applications scale. Curious to hear from other developers 👇 Do you use lazy loading in your React applications? #reactjs #frontenddevelopment #javascript #webdevelopment #reactperformance #softwareengineering #coding

Most developers are using Next.js… but not using it correctly. Here are 7 powerful Next.js concepts that most devs either ignore or misunderstand 👇 1️⃣ Stop using useEffect for data fetching With the App Router, you can fetch data directly in Server Components. Cleaner code. Better performance. Less client-side JS. 2️⃣ Server Components = Game Changer Zero bundle size impact Direct database/API access Faster page loads If you’re not using them, you’re missing the real power of Next.js. 3️⃣ Route Handlers can replace your backend You don’t always need Express or Node APIs anymore. Next.js can handle full-stack apps on its own. 4️⃣ Caching is EVERYTHING Understanding caching = performance boost Learn: force-cache no-store Revalidation This alone can 2x your app speed. 5️⃣ Streaming & Suspense = Better UX Render parts of your UI instantly instead of waiting for everything. Users feel your app is faster (even if it's not). 6️⃣ Edge vs Node runtime Edge = ultra-fast, global Node = full power Choosing the right one matters more than you think. 7️⃣ Middleware is underrated You can handle: Authentication Redirects Geo-based content All before your page even loads. 🚀 The truth? Next.js isn’t just a framework… it’s a full-stack system. But most devs are still using it like basic React. If you're learning Next.js right now: Focus less on tutorials… and more on how things actually work under the hood. Which of these are you already using? 👇 #NextJS #WebDevelopment #FrontendDevelopment #FullStackDeveloper #ReactJS #JavaScript #SoftwareDevelopment #CodingLife

🚀 Mastering useState in React (Beyond the Basics) Most developers use useState. Very few actually master it. If you want to write scalable, high-performance React apps… this is where it starts 👇 ⚡ 1. Think in “State Transitions”, Not Variables useState is not just a variable — it represents a change over time. 👉 Always ask: What triggers this change? ⚡ 2. Use Functional Updates Like a Pro Avoid stale state bugs in async scenarios. ✅ setCount(prev => prev + 1) ⚡ 3. Keep State Minimal (Golden Rule) The more state you store → the more re-renders you create. 👉 Store only what you cannot derive. ⚡ 4. Split State for Better Performance Don’t dump everything into one object. ❌ Bad: const [state, setState] = useState({ name: '', age: 0 }) ✅ Better: const [name, setName] = useState('') const [age, setAge] = useState(0) ⚡ 5. Avoid Unnecessary Re-renders Every state update triggers a re-render. 👉 Optimize using: useMemo useCallback Component splitting ⚡ 6. Know When NOT to Use useState Not everything belongs in state. 👉 Use: useRef → for mutable values constants → for static data 💡 Real Mastery Insight: useState isn’t about managing data… It’s about controlling rendering behavior. 🔥 If you master this, your React code becomes: ✔ Cleaner ✔ Faster ✔ Production-ready 📌 Follow for advanced React + Full Stack insights. #ReactJS #FrontendDevelopment #ReactHooks #JavaScript #WebDevelopment #PerformanceOptimization #CodingTips #FullStackDevelopment #SoftwareEngineering #LearnReact

Day 22: Error Boundaries in React In real-world applications, errors can happen anytime. A single error in one component can crash the entire UI. To handle this properly, React provides: Error Boundaries 📌 What are Error Boundaries? Error Boundaries are React components that catch JavaScript errors in their child component tree and display a fallback UI instead of crashing the whole app. ✅ Prevents complete app crash ✅ Displays fallback UI ✅ Improves user experience 📌 What Error Boundaries can catch? ✔ Errors in rendering ✔ Errors in lifecycle methods ✔ Errors in constructors of child components 📌 What Error Boundaries cannot catch? ❌ Errors inside event handlers ❌ Errors in async code (setTimeout, promises) ❌ Errors in server-side rendering 📌 Example of an Error Boundary import React from "react"; class ErrorBoundary extends React.Component { constructor(props) { super(props); this.state = { hasError: false }; } static getDerivedStateFromError(error) { return { hasError: true }; } componentDidCatch(error, info) { console.log("Error:", error); console.log("Info:", info); } render() { if (this.state.hasError) { return <h2>Something went wrong!</h2>; } return this.props.children; } } export default ErrorBoundary; 📌 How to use it? import ErrorBoundary from "./ErrorBoundary"; import App from "./App"; function Main() { return ( <ErrorBoundary> <App /> </ErrorBoundary> ); } Now, if any child component crashes, the app will show: 👉 "Something went wrong!" 📌 Why Error Boundaries are important? 🔥 Used in production apps 🔥 Prevents blank screens 🔥 Helps debugging errors #ReactJS #ErrorBoundary #FrontendDevelopment #JavaScript #WebDevelopment #CodingJourney #LearnInPublic

I kept wondering why my React app was calling the same API multiple times… 🤯 At first, I thought it was a small issue. But as the project grew, it became a real problem: * Repeated API calls * Too much state handling (loading, error, data) * Debugging became painful All because I was using `useEffect` for API calls. Then I tried something different — **React Query**. And honestly, it changed the way I handle server data: ✅ Automatic caching ✅ Built-in loading & error handling ✅ Cleaner, more maintainable code The biggest realization for me: 👉 *useEffect is not meant for managing server state.* I wrote a short article sharing what I learned and how I fixed these issues in a real project 👇 🔗 https://lnkd.in/gPMTcQBw If you're working with React, this might save you some debugging time. Would love to hear how you're handling API calls in your apps 👇 #React #JavaScript #PerformanceOptimization #WebDevelopment #ReactQuery

React is fast by default. But are YOU using it fast? Most React apps don't have a performance problem. They have a developer habit problem. Here are the advanced optimizations that separate senior devs from the rest: 1- Stop Abusing useEffect. Not everything belongs in a useEffect. Derived state? Compute it inline. Event-driven logic? Use handlers. useEffect is for synchronization, not control flow. 2- useMemo and useCallback. But only where it hurts. Wrapping everything in useMemo is not optimization, it's anxiety. Profile first. Memoize only when: A child component is wrapped in React.memo The value feeds a heavy computation It's a dependency in another hook 3- Code Splitting is Non-Negotiable Every route you don't lazy-load is bundle weight your user pays for. constDashboard=React.lazy(()=>import('./Dashboard')) Pair with <Suspense> and ship leaner initial loads. 4- Virtualize Long Lists Rendering 1,000 DOM nodes to show 10? That's a you problem. react-window or @tanstack/virtual renders only what's visible. Your scroll performance will thank you. 5- Avoid Anonymous Functions in JSX // ❌ New function reference on every render <Button onClick={()=>handleClick(id)}/> // ✅ Stable referenceconst handleItemClick =useCallback(()=>handleClick(id),[id]) React doesn't slow down. Unthoughtful patterns do. #React #Frontend #JavaScript #WebDevelopment #MERN #ReactJS #SoftwareEngineering #FrontendDevelopment

Most Node.js apps don't crash because of bad code. They crash because of bad error handling. Here's a pattern I use in almost every project: Instead of letting unhandled promise rejections silently kill your server, wrap your async route handlers in a reusable utility: const asyncHandler = (fn) => (req, res, next) => { Promise.resolve(fn(req, res, next)).catch(next); }; app.get('/user/:id', asyncHandler(async (req, res) => { const user = await getUserById(req.params.id); if (!user) throw new AppError('User not found', 404); res.json(user); })); app.use((err, req, res, next) => { res.status(err.status || 500).json({ message: err.message || 'Internal Server Error', }); }); That's it. One wrapper, one central error middleware, and your entire app handles errors consistently. The key insight: errors should flow to one place, not be scattered across every route with try/catch blocks copy-pasted everywhere. A custom AppError class lets you attach HTTP status codes and meaningful messages, so your API responses stay predictable for frontend teams. This also makes logging much easier — you intercept everything in one middleware and send it to whatever logging service you use. Small pattern, big payoff. Your teammates will thank you, and your on-call rotations will get a lot quieter. What's the error handling pattern you swear by in your Node.js projects — do you use something similar, or have you found a better approach? #nodejs #backend #javascript #softwaredevelopment #webdevelopment

Most React developers use keys wrong in lists. And it silently breaks their app. 😅 This is what everyone does: // ❌ Using index as key {users.map((user, index) => ( <UserCard key={index} user={user} /> ))} Looks fine. Works fine. Until it doesn't. The problem: If you add/remove/reorder items — React uses the index to track components. Index changes → React thinks it's a different component → Wrong component gets updated → Bugs that are impossible to debug. 💀 Real example: // You have: [Alice, Bob, Charlie] // You delete Alice // Now: [Bob, Charlie] // Index 0 was Alice, now it's Bob // React reuses Alice's DOM node for Bob // State gets mixed up! // ✅ Always use unique ID as key {users.map((user) => ( <UserCard key={user.id} user={user} /> ))} Rule I follow: → Never use index as key if list can change → Always use unique stable ID → Only use index for static lists that never change This one mistake caused a 2 hour debugging session for me. 😅 Are you using index as key? Be honest! 👇 #ReactJS #JavaScript #Frontend #WebDevelopment #ReactTips #Debugging

My React app crashed in production yesterday. The error? "Rendered fewer hooks than expected." The fix was exactly 2 lines of code 👇 I had this component: ❌ const MySection = () => { const store = useAppSelector(...) // Hook 1 if (!isVisible) return null // early exit const data = useMemo(...) // Hook 2 — SKIPPED! } When a user toggled visibility, React saw 2 hooks on render 1 but only 1 hook on render 2. Instant crash. 💥 The thing most devs don't realize: React doesn't track hooks by name. It tracks them by POSITION — like slots in an array. Slot 0 → useAppSelector Slot 1 → useMemo Skip one? Every hook below it reads the wrong slot's data. Think of it like filling a form top-to-bottom. Skip field 2, and field 3's answer lands in field 2's box. The fix: ✅ const MySection = () => { const store = useAppSelector(...) // Hook 1 — always runs const data = useMemo(...) // Hook 2 — always runs if (!isVisible) return null // safe here! } Move ALL hooks above ANY early return. That's it. 3 rules you must never break: → No hooks inside if/else blocks → No hooks after early returns → No hooks inside loops I found this same bug hiding in 2 other components in the same codebase. The app worked fine for months — until someone toggled the right button. What's the sneakiest React bug you've shipped to production? 👇 ——— ♻ Repost to save a fellow React dev from this bug 📕 Save this for your next code review 💡 Follow Abhay Rana for more visual React breakdowns #ReactJS #WebDevelopment #JavaScript #FrontendDevelopment #CodingTips