React Hooks: useMemo vs useCallback

React Hooks: Where Things Often Go Wrong React hooks are powerful, but many issues I see in codebases don’t come from React itself — they come from how hooks are used. A few patterns that usually cause trouble: • useEffect treated like a lifecycle replacement Not everything belongs in an effect. A lot of logic fits better in event handlers or during render. • Dependency arrays that grow endlessly When an effect depends on “everything,” it’s often a sign that responsibilities aren’t clear. • Effects that shouldn’t exist at all Some effects are only compensating for poor state placement or derived state. • Custom hooks that hide complexity Abstraction is useful, but hiding side effects inside hooks can make bugs harder to trace. • useRef used only for DOM access Refs are also great for storing mutable values that shouldn’t trigger re-renders. My takeaway: Hooks don’t replace good component design. Clear ownership of state and responsibilities makes hooks simpler — and bugs rarer ⚛️ #ReactJS #FrontendEngineering #Hooks #WebDevelopment #JavaScript #EngineeringInsights

⚛️ Improving React Performance with Lazy Loading As React applications grow, the bundle size can increase significantly. Loading all components at once can slow down the initial page load and impact the user experience. React Lazy Loading helps solve this problem by loading components only when they are needed, instead of including everything in the main JavaScript bundle. With tools like "React.lazy()" and "Suspense", React can split the code and dynamically load components when a user navigates to them. Benefits of React Lazy Loading: • Smaller initial bundle size • Faster page load • Better performance on slower networks • Improved overall user experience Optimizing how and when components load is a key step in building scalable and high-performance React applications. Reference from 👉 Sheryians Coding School #React #WebDevelopment #Frontend #JavaScript #Performance #SoftwareEngineering

🚨 React Hooks Tip: Always Call Hooks at the Top Level! 🚨 If you're working with React hooks, here’s a golden rule you must follow: 👉 Only call hooks at the top level of your functional component or custom hook. Avoid calling hooks inside loops, conditions, or nested functions. But why is this so important? React relies on the order of hook calls to keep track of state and effects between renders. When hooks are conditionally called, the order changes and React gets confused — causing bugs, unexpected behavior, or warnings like: 🔴 "React Hook 'useEffect' is called conditionally." For example, calling useState inside an if block means sometimes it runs — sometimes it doesn’t. React can't reliably associate state with the correct hook call anymore. How to fix it? ✔️ Always call your hooks unconditionally at the top level. ✔️ Move your conditional logic inside the hook (e.g., inside useEffect). ✔️ When you need conditional hooks, consider creating custom hooks that handle those conditions internally. By following this simple rule, your React components will stay predictable and bug-free — making your codebase easier to maintain and scale. Happy coding! 💡⚛️ #ReactJS #JavaScript #WebDevelopment #Frontend #ProgrammingTips #SoftwareEngineering

Want to learn more about React hooks? I recently stumbled upon BigFrontEnd.dev and have been really enjoying it. I’ve been spending some time in the React section, which has exercises where you predict what gets printed to the console when using React hooks. It’s been a great way to better understand how state updates work, when React re-renders a component, and how closures can affect values inside hooks. They also have a solid JavaScript section. I started exploring those to get a better feel for what actually gets logged when you combine things like console.log, setTimeout, and Promises. It’s been helpful for reinforcing how JavaScript handles execution order and the event loop. If you’ve been wanting to dig a little deeper into React hooks or brush up on JavaScript behavior under the hood, I highly recommend it Please let me know if there are any other great resources you use as well. #react #reacthooks #state #javascript

Day 2️⃣2️⃣ of #60DaysOfJavaScript Mastery is in the books! 📚✨ Today, I decided to stop just using React and start understanding the magic behind it. 🪄 We went deep into the world of Hooks! 🧵 Here’s the breakdown: ➡️ useState: The art of giving components a memory. From static to dynamic, one variable at a time. 🧠 ➡️ 💥 ➡️ useEffect: Taming the side effects! Whether it's fetching data or syncing with the outside world, learning to control when and how things run is a game-changer. ⚡🔄 ➡️ Custom Hooks: The ultimate power move. Abstracting complex logic into reusable, clean, and shareable chunks. It feels like building my own React toolkit! 🧰⚙️ Moving from "It works" to "This is why it works" feels incredibly satisfying. The component tree isn't so scary anymore when you know how to manage its state and lifecycle! 🌳 On to the next challenge! Who else is on a React journey right now? Let’s connect! 🤝 #JavaScript #ReactJS #WebDevelopment #FrontendDev #CodingJourney #useState #useEffect #CustomHooks #LearningToCode #Tech

You built a React component. Now how does it actually respond to the real world? Events. Re-renders. useEffect. These 3 connect everything together. 👆 Events — onClick, onChange, onSubmit (always camelCase, always a function reference) 🔁 Re-rendering — only state via setter triggers screen updates (regular variables won't!) ⚡ The Flow — click → setState → re-render → diff → DOM update 🎯 useEffect — run side effects like data fetching, timers, subscriptions 📋 Dependency Array — [] runs once, [count] runs when count changes, no array runs every time 🚀 Real pattern — loading state + useEffect fetch + dependency array The biggest beginner mistake? Using let count = 0 instead of useState(0) and wondering why the screen never updates. Save this. You'll come back to it. ♻️ Repost to help someone learning React. #React #useEffect #JavaScript #WebDevelopment #Frontend #LearnToCode

Probably one of the quietest dev tool you’ll ever meet , but but but , it got a point. Next.js + "use client" = chaos. Built Next Component Analyzer to stop the guessing game: Detects React hooks, Next navigation hooks, browser APIs Scans your components for JSX events Suggests Server vs Client Highlights unnecessary "use client" Works in JS or TS projects. Zero headache probably. Just clarity. https://lnkd.in/gGCcN9aa Your components will behave. You’ll be calmer. Your future self will nod approvingly. *P.S. If the analyzer roasts your component architecture… that's between you and your React hooks.* #NextJS #NodeJS #DevTools #OpenSource #JavaScript #Coding #SoftwareEngineering

React keeps evolving, but my brain doesn’t refresh as fast as the docs—so I built a compact React A–Z cheat sheet I can rely on instead of my memory. This is a high‑density desk reference for working React devs: JSX and rendering basics, state management (from useState/useReducer/Context to Redux Toolkit and Zustand), modern hooks, React 19 features, data fetching, forms, styling, testing, and architecture—condensed into a few focused pages. Instead of juggling 20 documentation tabs, you can keep this one sheet open next to your editor, quickly find the concept or keyword you need, and get back to shipping features faster. It’s not a tutorial, it’s a quick “React control panel” for people who already build apps and just want to move faster with fewer interruptions. #ReactJS #React19 #JavaScript #Frontend #WebDevelopment #MERNStack #ReactHooks #ReduxToolkit #TypeScript #NextJS #Remix #ReactNative #Programming #CheatSheet #SoftwareEngineering

Is React 19 finally going to kill useEffect for data fetching? 🤔⚛️ As a React developer, I've written the standard useEffect + fetch boilerplate more times than I can count. But looking at the new use() hook in React 19, things are about to get a lot cleaner. Take a look at the comparison below. 👇 Before: Managing state, loading flags, and dependency arrays. After: Simply passing the promise into use() and letting React handle the suspension. This means: ✅ Less boilerplate code ✅ No more missing dependency warnings ✅ Cleaner, more readable components I am definitely looking forward to refactoring some of my older projects to try this out. What do you guys think? Are you adopting the use() hook immediately, or sticking to libraries like React Query? Let me know! 👇 #reactjs #react19 #javascript #frontenddevelopment #webdev #coding #cleancode #webdevelopment #learning #codinglife

What if I told you that you don’t need to manually optimize your React code anymore? Cuz React compiler does it for you. What it does is simple. It automatically memoizes your components. The compiler looks at your code, figures out which values actually change between renders and which ones stay the same, and then reuses the stable ones instead of recomputing them every time. But do you know how it actually does that magic under the hood??? Soo..During the build step, the compiler analyzes your component and builds a dependency map of variables, props, and computations. It understands what depends on what. Once it knows that, it can safely cache parts of your component and skip work when nothing relevant changed. So the optimizations we used to write manually with useMemo() or React.memo now get inserted automatically. If you wanna try it in your project, it’s actually pretty easy. Install the compiler plugin: ☘️ npm install babel-plugin-react-compiler Then add it to your Babel config: ☘️ plugins: ["babel-plugin-react-compiler"] That’s it... Write normal React. The compiler quietly optimizes things during the build Follow Sakshi Jaiswal ✨ for more quality content ;) #Frontend #React #Sakshi_Jaiswal #FullstackDevelopment #javascript #TechTips #ServerComponents #UseMemo #UseCallback