Optimize React List Performance with React-Virtualized

Today everything started to feel… more real. React Masterclass (Day 5). I began with: • Sharing state between components • Passing functions as props • Understanding how React handles state updates But instead of stopping there, I asked: How would this actually work in a real app? 💰 So I built a Budget Tracker: • Set initial balance • Add expenses that reduce it in real-time • Dynamic UI based on current state • Data persisted using localStorage • Clean updates using functional state 💡 Key concepts that clicked: • Lazy initialization (run logic only once) • Functional updates (state based on previous state) • Derived values (calculating remaining balance) Small concepts → Real product thinking. #React #Frontend #WebDevelopment #LearningInPublic #JavaScript

🧠 Most React apps scale fine at the start, Until state becomes messy, unpredictable, and hard to manage. 👉 Read the full guide 🔗 📌 What you’ll learn: https://shorturl.at/jtKRp ➥ Why poor state design is the biggest bottleneck in scaling React apps ➥ How to separate UI state vs server state effectively ➥ When to use local state, context or state libraries ➥ Patterns to avoid prop drilling and unnecessary re-renders ➥ Practical strategies to build clean, scalable state systems ✨✍ Written by: Harsh Chauhan #ReactJS #StateManagement #FrontendArchitecture #WebDevelopment #JavaScript #ScalableSystems #Engineering

⚠️ Your React App Isn’t Slow… You’re Just Rendering Too Much. I used to think UI lag was normal as my React projects grew. Turns out — I was wrong. The real problem? 👉 Unnecessary re-renders killing performance. Here’s what I changed: • Used React.memo to stop useless re-renders • Avoided redundant state updates • Fixed messy useEffect dependencies • Broke large components into smaller reusable pieces And the impact? • Faster UI • Better performance • Cleaner codebase Biggest lesson: React doesn’t slow down — poor optimization does. Now I’m more focused on how components render, not just what they render. #reactjs #webdevelopment #mernstack #frontend #performance #javascript

Most React apps render everything immediately, even components users haven’t scrolled to yet. That means unnecessary work for the browser and slower pages. Here is a custom React hook using Intersection Observer that renders components only when they enter the viewport. Perfect for: • lazy-rendering sections • dashboards with heavy widgets • charts and media components • improving scroll performance • reducing initial load cost Small hook. Noticeable performance win. Try it in your next project and you’ll feel the difference. #reactjs #javascript #webperformance #frontenddevelopment #reacthooks #softwaredevelopment #webdev #codingtips #devcommunity #intersectionobserver #performanceoptimization

Is poor state architecture the real reason your React app is hard to scale? Full guide: https://lnkd.in/d9Ayg3gM ➤ In most codebases, yes. • Props: parent-to-child only • Local State: UI & form interactions • Context API: auth, themes, no prop drilling • Redux: large-scale apps only • Hooks: performance & global state access ➤ Golden rule: keep state as local as possible. ➤ Simplicity before premature complexity. #ReactJS #FrontendDevelopment #StateManagement #Redux #JavaScript

🚀 Just launched: react-state-vitals A zero-config memory & render monitor for React apps. While working on production apps, I kept asking: 👉 Why is this component re-rendering so much? 👉 Which store is growing in memory? 👉 Where is my performance actually going? So I built a tool to make this visible — instantly. 🧠 react-state-vitals gives you a live floating panel in development: • 📊 Store size tracking (Zustand, Context, React Query) • 🔁 Re-render counts per component • 🧬 JS heap usage insights • ⚡ Zero setup — just install and see Think of it as: 👉 “Vitals for your React state & memory” 📦 Try it here: https://lnkd.in/gU692hyT 🔥 Next I’m planning: • DevTools-like overlay • Identify memory-heavy components in real time • Visual performance timeline Would love feedback from fellow devs 🙌 What would you want this to track next? #React #JavaScript #Frontend #WebPerformance #OpenSource #NextJS #Zustand

React is easy to start… But hard to master. At first, it’s just components and props. But then you realize the real game: 👉 State management 👉 Performance optimization 👉 Re-render control A small mistake in structure can slow down your entire app. What I’ve been focusing on: ✔ Writing reusable components ✔ Avoiding unnecessary re-renders ✔ Keeping logic clean and scalable Because good UI isn’t just about looks… It’s about performance + maintainability. #ReactJS #FrontendDevelopment #JavaScript #WebDevelopment #UIUX

React is slow. At least, that’s what people say when their app starts lagging. But in most cases… React isn’t the problem. Recently, I debugged a performance issue that appeared to be a “React bottleneck”. Turns out 👇 ▪️ Multiple forced reflows & repaints ▪️ Layout thrashing from DOM reads/writes ▪️ Unoptimized rendering triggered by side effects React was just doing its job. The browser was struggling. What actually helped: ✔️ Batching DOM operations properly ✔️ Avoiding layout-triggering CSS changes ✔️ Measuring before mutating (not the other way around) The takeaway: 🏆 If you don’t understand how the browser renders, every framework will feel “slow”. Have you ever blamed React for something that wasn’t actually React? #reactjs #frontend #webperformance #webdevelopment

⚡ Why Most React Apps Feel Slow (And How to Fix It) Many developers think performance issues come from React itself. But in reality — it’s usually how we use it. Here are some common mistakes 👇 🔴 Unnecessary Re-renders Components re-render more than they should. 👉 Use React.memo, useMemo, useCallback wisely. 🔴 Large Component Trees Everything in one component = performance drop. 👉 Split into smaller, reusable components. 🔴 Ignoring Lazy Loading Loading everything at once hurts UX. 👉 Use React.lazy() and dynamic imports. 🔴 Heavy State Management Too much global state = unnecessary updates. 👉 Keep state as local as possible. 🔴 No Virtualization Rendering long lists directly? Big mistake. 👉 Use libraries like react-window. 💡 Performance is not about optimization later — it’s about writing better code from the start. What’s the biggest performance issue you’ve faced in React? 👇 #ReactJS #Frontend #WebDevelopment #JavaScript #Performance

🚀 I improved my Next.js app performance without adding any new library… Most developers think performance = install more packages. I used to think the same. But recently, while working on a production project, I focused on fixing fundamentals instead of adding complexity 👇 ✅ Reduced unnecessary re-renders ✅ Optimized API calls (no duplicate fetching) ✅ Used proper dynamic imports in Next.js ✅ Cleaned up unused components & heavy logic 📉 Result? - Faster page load - Better Lighthouse score - Smoother user experience 💡 Biggest lesson: Performance is not about tools — it's about understanding your code deeply. Sometimes, the best optimization is removing things, not adding. Curious — what’s one performance mistake you’ve seen developers make often? #reactjs #nextjs #webdevelopment #frontend #performance #javascript