Work backwards from the round structure most Indian MNCs and product companies follow: an online coding/DSA round, a technical round on frontend and backend fundamentals, a machine-coding or system discussion round, and HR. Build strength in JavaScript fundamentals (closures, event loop, promises), React (hooks, state management), backend with Node.js/Express or Django, REST API design, and SQL/MongoDB basics. Full stack developer interview questions almost always include a project deep-dive, so be ready to explain your architecture, your trade-offs, and a tough bug you fixed. Two deployed projects, consistent DSA practice, and a couple of mock interviews will put you ahead of most candidates.

At 2 years, interviewers test depth, so revise your own work first — know every line of your resume projects, why you picked MongoDB over MySQL or Express over Django, and how you would scale what you built. Then cover JavaScript internals, React performance basics, Node.js API design, authentication (JWT, OAuth), Git workflows, Docker basics, and medium-level DSA. Prepare STAR stories for a conflict, a deadline, and a production issue you handled. Practicing from real MNC interview sets helps you spot the pattern of rounds quickly instead of studying randomly.

Fresher rounds usually stay close to fundamentals: HTML/CSS (flexbox, responsiveness), JavaScript (var/let/const, hoisting, closures, promises, event loop, ES6), React (components, props vs state, useState/useEffect, virtual DOM), Node/Express basics, SQL joins, and one or two easy-to-medium DSA problems like string reversal or finding duplicates. Expect "walk me through your project," "what was the hardest bug you fixed," and HR questions about relocation and salary. Solving a structured fresher question bank with model answers is far more effective than collecting random questions from ten different sites.

At 5 years, the focus shifts from definitions to design: you may be asked to build a URL shortener, e-commerce cart, or chat app on a whiteboard, and discuss microservices vs monoliths, caching with Redis, message queues, load balancing, CI/CD, Docker, database indexing, and security (JWT, OAuth2, CORS, XSS). DSA is usually one medium-level problem, but clean, readable code matters. Also prepare leadership stories — mentoring juniors, handling a production outage, or leading a migration — with numbers attached, like "cut API response time by 30%."

Treat it as two layers. First, Java core: OOPs, collections (HashMap internals, ConcurrentHashMap), exception handling, Java 8 streams and lambdas, multithreading basics, and JVM memory. Second, the stack: Spring Boot (annotations, dependency injection, Spring Data JPA, REST controllers), Hibernate (lazy vs eager loading, the N+1 problem), SQL, and a frontend like React or Angular with TypeScript. Solve DSA in Java itself, deploy one Spring Boot + React project with JWT authentication, and revise from an authenticated Java full stack question set so you know what MNC rounds actually repeat.

Most PDFs floating around Telegram groups and Drive links are outdated or copy-pasted without proper answers, so check the date and depth before trusting them. Better options are structured sources: well-maintained GitHub repos for coverage, and curated, authenticated question banks compiled from real MNC interviews — several Topmate creators sell exactly these for full stack, frontend, and backend roles, with model answers included. Whichever you pick, don't just read the answers; write them out and speak them aloud, because that is what actually sticks in the interview room.

Prioritize the recurring set: virtual DOM and reconciliation, functional vs class components, props vs state, keys in lists, controlled components, lifting state up, context API vs Redux, error boundaries, and performance optimization with memo, useMemo, and lazy loading. Then add machine-coding practice — a counter, a todo list, a debounced search bar — because most MNCs now include a live React round. Reading answers is not enough; write each one out and be able to explain the "why" behind every hook you use.

Freshers are tested on: JSX, the virtual DOM, functional vs class components, props vs state, useState and useEffect basics, conditional rendering, lists and keys, controlled forms, and prop drilling. There is usually a small live task — build a counter, toggle, or todo app — plus questions on your own projects like "why did you choose React for this?" Know your resume projects inside out, because fresher React rounds lean heavily on what you have actually built.

Experienced rounds skip definitions and go straight to scenarios: how would you speed up a slow React app (memoization, code splitting, windowing for long lists, bundle analysis)? When would you pick Redux Toolkit over Context or React Query? How do you structure a large codebase, handle testing with Jest and React Testing Library, and manage server state, error handling, and accessibility at scale? You may also be asked to refactor messy code live or review a snippet, so practice explaining trade-offs out loud rather than just naming concepts.

The most repeated ones are: what hooks are and why they replaced class lifecycles, the rules of hooks, useState with lazy initialization, useEffect dependency arrays and cleanup, useCallback vs useMemo, useRef use cases, useContext, useReducer vs useState, useLayoutEffect vs useEffect, stale closures, and writing custom hooks like useDebounce or useFetch. Expect to actually code a custom hook in the interview, so practice building a few from a blank file rather than memorizing definitions.

GitHub question repos are a good checklist, but they have three gaps: many answers are outdated, explanations are often shallow or copied, and nothing tells you whether your own answers sound convincing. Use a repo for coverage, then close the gaps by coding the machine-round problems yourself, doing at least one or two mock interviews, and, if you are targeting specific MNCs, going through an authenticated question set from real interviews — a quick 1:1 prep call with someone who has cracked those rounds can pinpoint your weak spots in an hour.

Expect four buckets: HTML (semantic tags, forms, accessibility basics), CSS (box model, flexbox vs grid, position, specificity, media queries, pseudo-classes), JavaScript (data types, == vs ===, hoisting, closures, promises and async-await, the event loop, array methods, ES6 features), and the DOM (event bubbling, delegation, localStorage vs cookies). Most companies also run a short machine-coding or layout round — build a responsive header with a sidebar, tabs, an accordion, or a countdown timer. Two or three well-built projects on your resume make these rounds much easier.

At 3 years, interviewers probe engineering maturity: Core Web Vitals and performance work (code splitting, lazy loading, image optimization), TypeScript (generics, interfaces vs types, utility types), state management with Redux Toolkit or modern alternatives, component design patterns, testing with Jest and React Testing Library, security basics like XSS and CSRF, and build tools such as Webpack or Vite. Bring one story with a metric — "improved Lighthouse score from 60 to 90" — because experience rounds reward proof, not vocabulary.

Keep it to 60–90 seconds with a simple arc: your current role and tech stack, one or two highlights with numbers, and why this role excites you. For example: "I'm a full stack developer working mainly with React and Node; recently I rebuilt our checkout flow and cut load time noticeably, and I'm now looking to work on larger-scale products, which is why this role stood out." Don't recite your resume from school onwards, don't ramble past two minutes, and tailor the final line to each company. Rehearse it aloud until it sounds conversational, not memorized.

Name a genuine, non-critical weakness, show that you have already worked on it, and give evidence. For instance: "I used to jump into coding before scoping features fully; now I write a short design note and get a quick review first, which has reduced rework on my team." Avoid rehearsed clichés like "I'm a perfectionist," avoid red flags such as missing deadlines or clashes with managers, and never say you can't think of one. Interviewers are checking honesty and self-awareness, not perfection.