Stop Using JSON.parse(JSON.stringify(obj)) for Deep Copy

Stop memoizing everything in React. You're probably making your app slower, not faster. 🎯 We've all been there. We read about React performance best practices and start wrapping everything: 💭 The thought process: "I'm being proactive about performance!" 🚫 Reality: This component is now slower than without memoization. Here's what most developers don't realize: memo(), useMemo(), and useCallback() aren't free. Every time your component renders, React has to: - Run comparison logic to check if props/dependencies changed - Store previous values in memory - Execute the equality checks For a simple component like the one above that renders in microseconds, the memoization overhead is often MORE expensive than just letting the component re-render naturally. When memoization actually helps: ✅ Components with expensive render logic (complex calculations, large lists) ✅ Heavy component trees that cascade re-renders ✅ Stabilizing references for dependency arrays in useEffect ✅ Preventing expensive child components from re-rendering When it's premature optimization: ❌ Simple components with primitive props ❌ Components that render quickly anyway ❌ "Just in case" memoization without profiling first The React 19 game-changer: Here's the exciting part - React 19 introduces the React Compiler, which changes everything. The compiler automatically analyzes your code and applies memoization where it actually helps, without you having to think about it. No more manual useMemo, useCallback, or memo() in most cases. The compiler handles it intelligently, only optimizing where there's a real benefit. My approach: 1. Build first - Write clean, readable code 2. Profile when needed - Use React DevTools when you notice actual performance issues 3. Optimize with data - Fix the specific bottlenecks you identify, not theoretical ones Remember: React is already fast by default. Premature optimization adds cognitive overhead to your code and often delivers zero performance benefit. 💡 The best optimization is the one you don't have to write. What's your experience with React memoization? Have you caught yourself over-optimizing? 💭 #React #WebDevelopment #JavaScript #Performance #ReactJS #React19

🚀 Day 5 – Backend Journey | Handling URLs in Node.js 🔥 Today was all about UNDERSTANDING how the web actually works 🌐💥 I learned how to handle URLs in Node.js without any framework — pure core concepts 💪 ✨ What I explored today: 🔹 Parsed URLs using url.parse(req.url, true) 🔹 Used pathname for routing (/, /about) 🔹 Extracted query parameters from URL 🔹 Built dynamic responses like: /about?myname=Faiz ➡️ Output: Hi, Faiz 😎 🔹 Logged every request using fs.appendFile() 🔹 Learned why browsers send /favicon.ico requests 🔹 Realized how frameworks like Express.js work internally 💡 Day by day, concepts are getting clearer. Less shortcuts, more fundamentals 💯 Backend grind is ON 🔥 Day 5 DONE ✅ #NodeJS #BackendJourney #Day5 #JavaScript #WebDevelopment #LearningByBuilding #MERN #100DaysOfCode 🚀

⚛️ The React Bug That Confused Me for DAYS… Ever seen this error? 👉 “Cannot read property ‘map’ of undefined” I had the data. I had the API. Yet my React app kept breaking. The problem? componentWillMount() vs componentDidMount() 🚫 componentWillMount() (The Trap) ❌ Deprecated since React 16.3 ❌ Not safe for async rendering ❌ React does not wait for API calls here ❌ Component renders with empty data 💥 Leads to runtime errors & confusion React renders first. Your data comes later. ✅ componentDidMount() (The Fix) ✔️ Runs after the first render ✔️ Safe place for API calls ✔️ Called once on the client ✔️ Lets you control loading states properly ✔️ No unexpected crashes 💡 The Big Lesson React is async-first. Your UI must survive before the data arrives. Once this clicked, my projects suddenly worked—and React finally made sense. If you’ve ever struggled with lifecycle methods or Hooks, you’re not alone. 👇 Have you hit this bug before? Let’s talk. #ReactJS #JavaScript #Frontend #WebDev #LearningInPublic #CodeNewbie #ReactHooks

Great reminder. We often inherit these 'quick fixes' from legacy StackOverflow answers without questioning if the answers are completely relevant to our queries. Swapping these out is a low-effort, high-impact way to improve codebase reliability. If you're still seeing this in your PRs, it might be time for a quick internal documentation update or an ESLint rule.

Your frontend might not be slow. It might just be forgetful. Ever noticed this? • Page loads in 10 seconds • You open a detail view • You go back • Another 10 seconds At that point, the backend isn’t the villain. What’s actually happening is simple: Your frontend is re-fetching the same API again and again because the data dies with the component. Fetching data ≠ caching data. Most of the time: • Component unmounts • State is destroyed • API fires again • Users wait… again This is one of the most common performance mistakes I see in React, Next.js, and SPAs. The fix isn’t complex. You just need data to live outside the component lifecycle: • Query caching • Global state • Framework-level caching I wrote a short, practical breakdown here 👇 🔗 https://lnkd.in/gEwpQfkR If your app keeps calling the same slow endpoint, it’s not a performance issue. It’s a missing caching strategy. #FrontendDevelopment #WebPerformance #ReactJS #NextJS #JavaScript  #SoftwareEngineering #SystemDesign #WebDev #DeveloperExperience  #Caching #PerformanceOptimization

Simpler code is better. So, you're building apps with React - and let's be real, who doesn't love the idea of keeping their code clean and easy to read? But have you ever stopped to think about just how many imports you're dealing with? It's crazy, right? You're importing libraries just to toggle a CSS class, and before you know it, your code is looking cluttered. What if I told you there's a way to make your code cleaner, without all those extra imports? You can use a new way of writing JSX that's more straightforward. For instance, take a look at this example: you can write a Card component with just a few lines of code, and it's actually pretty elegant. It's all about using the language to your advantage - and in this case, that means using JSX in a way that feels more natural. You define your Card component, and then you're using a simple div with some conditional classes, like 'border-blue-500' if it's active, or 'opacity-50 cursor-not-allowed' if it's disabled. And the best part? You don't need any extra imports to make it work. To get started, you just need to tell your compiler to use the new runtime - which is as simple as adding a couple of lines to your tsconfig.json or jsconfig.json file. You add "jsx": "react-jsx" to your compiler options, and then you add "jsxImportSource": "clsx-react". And that's it - you're good to go. You can even use this approach with Vite or Babel, which is pretty cool. The benefits are clear: you're removing unnecessary imports, you're getting rid of visual clutter in your JSX, and you're getting back to writing simple, straightforward code. It's a game-changer, trust me. So why not give it a try and see how it works for you? Source: https://lnkd.in/gSs6398r Optional learning community: https://lnkd.in/geSQUpYM #React #JSX #CleanCode

Most developers think Array.prototype.map() is always safe. It’s not. If you use map() just for side effects, you’re lying to the next person reading your code. Example of a common mistake: users.map(user => { sendEmail(user); }); map() is meant to transform data, not execute actions. The correct tools: • forEach() → side effects • map() → transformation • reduce() → accumulation • some() / every() → condition checks Better code: users.forEach(sendEmail); Why this matters: • Clear intent makes code easier to reason about • Prevents accidental misuse in async flows • Improves readability and maintainability Clean code is not about cleverness. It’s about being honest with your abstractions. #javascript #cleanCode #webdev #frontend #nodejs

Most messy React code doesn’t come from “bad developers.” It comes from poor boundaries. I see components that: • fetch data • manage UI state • handle side effects • format data • render JSX • handle business rules …all in one place. When everything lives together: • bugs hide easily • refactoring feels scary • components become impossible to test • every change breaks something else Clean React usually means: • components focused on rendering • logic extracted into hooks • data handling clearly separated • state kept where it actually belongs It’s not about writing more code. It’s about deciding what belongs where. 💬 Question: What’s the biggest “too-much-responsibility” component you’ve ever had to refactor? #ReactJS #FrontendDevelopment #CleanCode #WebDev #SoftwareEngineering #JavaScript

Are you still writing React like it’s 2021? It’s time to unlock the "hidden" tier.🙈 Stop sleeping on React’s full potential. ⚛️💤 We all know useState and useEffect. They are the bread and butter of modern React development. But if you stop there, you are leaving massive performance gains and cleaner architecture on the table. The React ecosystem evolves fast. While many are still debating project structure, the core team has shipped incredible tools that often fly under the radar in daily work. Here are 3 "hidden" (highly underutilized) gems you should start using today: 💎 1. The Performance Smoother: useDeferredValue Are your heavy UI components causing typing lag in your inputs? Stop reaching for manual lodash debouncing. useDeferredValue lets you tell React: "Update the input immediately, but that expensive list rendering below it can wait a sec." It keeps your UI buttery smooth by deprioritizing heavy updates automatically. 💎 2. The External State Saviour: useSyncExternalStore Still struggling to connect React to non-React state (like browser APIs, external stores like Zustand/Redux outside components, or Web Sockets) without "tearing" issues? This is the officially sanctioned hook for subscribing to external data sources. It ensures your component always renders consistently with the latest external data, even during concurrent rendering. It's complex under the hood so you don't have to be. 💎 3. The (Upcoming) Form Revolution: React 19 Actions & useOptimistic Okay, a sneak peek at the near future. Form handling in React has notoriously required too much boilerplate setState glue. React 19 is bringing "Actions" to client-side React. Combined with useOptimistic, you can show immediate UI updates (like adding a comment instantly) while the server request processes in the background, and automatically rollback if it fails. No manual loading state spaghetti required. 👇 The takeaway: Don't just stick to the tutorials you read three years ago. Explore the docs. The tools to build faster, better apps are already there. Which of these features are you using in production? Which one is totally new to you? Let me know in the comments! #ReactJS #WebDevelopment #JavaScript #Frontend #ProgrammingTips #React19

 A JavaScript Quirk That Still Breaks Apps 🚨 This JavaScript Line Looks Innocent… But It Breaks Apps typeof null === "object" Yes. This is true 😐 And no — it’s not a feature. It’s JavaScript’s oldest mistake. 🤯 Why this happens Back in the early days of JavaScript, null was stored as a zero pointer. JavaScript never fixed it… because fixing it would break the internet 🌍 💥 Real-world bug example if (typeof data === "object") { process(data); } 💣 This also runs for null 💣 App crashes silently 💣 Debugging takes hours ✅ The correct check if (data !== null && typeof data === "object") { process(data); } 🧠 Takeaway JavaScript isn’t weird. It’s backward-compatible. Knowing these quirks is what separates: 👉 beginners 👉 from confident developers 👉 Follow me for daily JavaScript clarity 🚀 #JavaScript #WebDevelopment #Coding #Frontend #Developers