Nidhi Jagga’s Post

🚨 What I prepared for the interview vs What the interviewer actually asked Before the interview, I was revising all the “important” stuff. React lifecycle, advanced hooks, project architecture, performance tricks, even some DSA questions. I thought the interviewer would definitely go deep into complex topics. But when the interview started… the direction was completely different. The interviewer didn’t touch anything fancy. He calmly started with: 🔹 JavaScript • What is hoisting? • What is closure? • Difference between map and reduce • Difference between slice and splice • What is filter? 🔹 React • What is Virtual DOM? • What is dependency array in useEffect? • Why do we use keys in React lists? 🔹 Backend / Node.js • What is CORS? • What is JWT? • What is middleware? • What is the purpose of next()? No tricky questions. No puzzles. No “write code on the spot”. Just pure fundamentals. And honestly, that surprised me. Because I realized something important in that moment: 👉 We often over-prepare advanced topics 👉 And under-prepare the basics we use every day The interviewer wasn’t checking how many tools I know. He was checking how clearly I understand what I already use. That interview felt like a mirror. It showed me that interviews are less about “how much” you know and more about how well you know it. ✨ My biggest learning from this experience: Strong fundamentals in JavaScript, React, and Node.js can carry you through most interviews. Now my preparation style has changed: More focus on basics. More focus on explaining concepts clearly. Less focus on memorizing advanced things. If you’re preparing for interviews, don’t make the same mistake I did. 📌 Revise the basics before anything else. #JavaScript #ReactJS #NodeJS #InterviewExperience #InterviewPreparation #FrontendDeveloper #WebDevelopment #LearningInPublic #MERNStack

Day 42/365 JS Interview Question 🔥 👉 Shallow Copy vs Deep Copy 🔹 Shallow Copy Copies only the first level. If there’s a nested object, it still shares the same reference. (Yes, spread {...obj} is shallow 👀) 🔹 Deep Copy Creates a completely separate clone. (structuredClone() does this properly.) In interviews, they don’t stop here. The real discussion usually goes like: 1). Why does spread fail with nested objects? 2). Have you ever faced a bug because of shallow copy? 3). Why isn’t JSON.parse(JSON.stringify()) always safe? 4). How does this affect React re-renders? When would deep cloning actually hurt performance? That’s where the conversation becomes interesting. Senior frontend isn’t about knowing syntax. It’s about understanding how memory and references actually work. #javascript #jsinterview #frontend #webdevelopment #interview #deepcopy #shallowcopy #frontenddevelopment

React JS Interview Practice – Episode 07 One of the most frequently asked React interview questions: 👉 How do you fetch data from an API and display it in a component? In this video, I’ve explained: ✔ Fetch API integration ✔ useEffect hook usage ✔ useState for data handling ✔ Managing asynchronous operations ✔ Rendering dynamic API data Understanding API integration is essential for every frontend developer. This practical example will help students and job seekers build strong React fundamentals. 📌 Part of: 30 Days Coding with The Vinia 🎯 Goal: Learn React through real interview-based practice. If you're preparing for React interviews or strengthening your frontend skills, this series is for you. 💬 Comment “Interested” if you want the full practice roadmap. 🔔 Follow for more React and frontend content. #ReactJS #ReactInterview #FrontendDevelopment #WebDevelopment #JavaScript #APIFetch #CodingPractice #TechEducation

Are React Hooks Synchronous or Asynchronous? Repeated Interview Questions | Day 23 This is one of the most commonly asked React interview questions — and many developers get confused. Here’s the clear breakdown 👇 ✅ Hooks execute synchronously during render ✅ useState updates are asynchronous (batched) ✅ useEffect runs after render ✅ useLayoutEffect runs before browser paint ✅ State updates happen in the next render cycle 💡 Interview Tip: Hooks run synchronously, but state updates inside them are asynchronous. Understanding this difference helps avoid: Stale state bugs Unexpected console values Performance issues Mastering these fundamentals makes you a stronger React developer 💪 What other React interview questions should I explain next? 👇 👨💻 Follow for daily React, and JavaScript  👉 Arun Dubey #ReactJS #FrontendDeveloper #JavaScript #Day23 #ReactHooks #InterviewPreparation

🚀 Did the interviewer ask questions? : What’s the Real Difference? Class vs Functional Component —   Day17 Agar aap React interview ki preparation kar rahe ho, to ye question almost guaranteed hai 👇 👉 Class Component vs Functional Component Earlier, we used Class Components with: • this.state • constructor() • render() method • More boilerplate code But today, developers prefer Functional Components because: • Simple JavaScript functions • useState & other Hooks • No this keyword • Cleaner & shorter code 💡 Best Interview Answer (Short & Smart): Class components use ES6 classes and manage state using this.state and lifecycle methods. Functional components use Hooks like useState and useEffect to manage state and side effects. Modern React applications prefer functional components because they are cleaner, shorter, and easier to maintain. 🔥 Same work. Less code. Better readability. 👨💻 Follow for daily React, and JavaScript 👉Arun Dubey If you're preparing for React interviews, save this post 👇 #ReactJS #FrontendDevelopment #JavaScript #ReactInterview #SoftwareDeveloper 🚀

⚛️ Most over-asked React interview question: “What is the difference between useEffect and useLayoutEffect?” What interviewers are actually testing 👇 Not the definition. Not the syntax. They want to know if you understand: • When effects run • How rendering works • What causes flickering • And when blocking the paint is dangerous ⚛️ Answer: useEffect vs useLayoutEffect Both run after React renders. The difference is when they run. 🔖useEffect - → Runs after the browser paints the screen. → Non-blocking. → Best for data fetching, subscriptions, logging. 🔖useLayoutEffect - → Runs before the browser paints. → Blocks the paint until it finishes. → Useful when you need to measure or modify the DOM immediately. Example: If you need to measure element size and adjust layout before the user sees it — use useLayoutEffect. In most cases, useEffect is enough. But the rule is: Use useLayoutEffect only when timing really matters. 🧠 #ReactJS #FrontendDevelopment #JavaScript #TechInterviews #SoftwareEngineering

React Handwritten Notes From Basics to Advanced (Interview Focused) Learning React can feel overwhelming especially when preparing for frontend interviews. That’s why I created these React handwritten notes to simplify complex concepts into easy-to-remember diagrams, flow explanations, and real-world examples. These notes cover everything from core React fundamentals to advanced performance and architecture concepts, making them perfect for quick revision, deep understanding, and interview preparation. 📌 Ideal for:- React Beginners Frontend Developers Interview Preparation (L1 → Senior Level) Quick Revision before interviews 📚 Topics Included JSX & Components Props vs State Hooks (useState, useEffect, useMemo, useCallback) Lifecycle & Rendering Controlled vs Uncontrolled Components Performance Optimization React Architecture & Best Practices #ReactJS #FrontendDevelopment #ReactNotes #HandwrittenNotes #InterviewPreparation #JavaScript

React Handwritten Notes From Basics to Advanced (Interview Focused) Learning React can feel overwhelming especially when preparing for frontend interviews. That’s why I created these React handwritten notes to simplify complex concepts into easy-to-remember diagrams, flow explanations, and real-world examples. These notes cover everything from core React fundamentals to advanced performance and architecture concepts, making them perfect for quick revision, deep understanding, and interview preparation. 📌 Ideal for: React Beginners Frontend Developers Interview Preparation (L1 → Senior Level) Quick Revision before interviews 📚 Topics Included JSX & Components Props vs State Hooks (useState, useEffect, useMemo, useCallback) Lifecycle & Rendering Controlled vs Uncontrolled Components Performance Optimization React Architecture & Best Practices #ReactJS #FrontendDevelopment #ReactNotes #HandwrittenNotes #InterviewPreparation #JavaScript

I once walked out of a #React interview thinking: “I know React… why did this feel so hard?” The questions weren’t tricky. They were fundamental. ❌ “Explain Virtual DOM” ❌ “Props vs State” ❌ “Why keys matter?” ❌ “useEffect dependencies?” That’s when I realized something important 👇 Most React interviews don’t test how much you’ve built — They test how clearly you understand what you already use every day. Curated with: ✅ Basic → Intermediate → Advanced questions ✅ Clear, interview-friendly explanations ✅ Real concepts interviewers care about Perfect if you’re: 🎯 Preparing for frontend/full-stack interviews 🎯 Switching companies 🎯 Revising React after long project work Because in interviews, confidence comes from clarity, not cramming. 📎 ReactJS Interview Questions PDF attached 👉 Follow Ankit Sharma Sharma for interview prep, system design, and practical engineering insights. #ReactJS #FrontendInterviews #JavaScript #WebDevelopment #SDE #InterviewPreparation