𝗖𝗼𝗺𝗽𝗮𝗻𝘆: Capgemini
𝗥𝗼𝗹𝗲: MERN Stack Developer
𝗘𝘅𝗽𝗲𝗿𝗶𝗲𝗻𝗰𝗲: 2–4 Years
𝗦𝘁𝗮𝗰𝗸: React.js + Node.js + Express.js + MongoDB
𝗛𝗶𝗿𝗶𝗻𝗴: LinkedIn Job Posting
𝗥𝗼𝘂𝗻𝗱 𝟭 – 𝗝𝗮𝘃𝗮𝗦𝗰𝗿𝗶𝗽𝘁 & React.js
• Explain hoisting in JavaScript with let, const and var
• What is the difference between shallow copy and deep copy?
• Explain event bubbling and event capturing
• What are higher-order functions in JavaScript?
• What is the difference between Promise.all(), Promise.allSettled() and Promise.race()?
• How does React reconciliation work?
• Explain React.memo(), useMemo() and useCallback()
• What is prop drilling and how can you avoid it?
• How does React Context API work?
• How would you improve the performance of a large React application?
𝗗𝗦𝗔:
• Contains Duplicate
• Longest Substring Without Repeating Characters
• Merge Two Sorted Arrays
• Product of Array Except Self
𝗥𝗼𝘂𝗻𝗱 𝟮 – Node.js | 𝗘𝘅𝗽𝗿𝗲𝘀𝘀 | 𝗠𝗼𝗻𝗴𝗼𝗗𝗕
• Why is Node.js suitable for I/O-heavy applications?
• Explain the difference between process.nextTick() and setImmediate()
• How does Node.js handle concurrent requests?
• What are streams in Node.js and where would you use them?
• How do you structure a scalable Express.js application?
• Explain Express.js error-handling middleware
• How would you secure a REST API?
• Access token vs refresh token — what is the difference?
• What are MongoDB compound indexes and when should you use them?
• Explain MongoDB transactions and when they are required
• What is the difference between find(), findOne() and aggregate()?
• How would you design an efficient search API?
𝗗𝗦𝗔:
• Detect Cycle in a Linked List
• Search in Rotated Sorted Array
• Top K Frequent Elements
• Merge Intervals
𝗥𝗼𝘂𝗻𝗱 𝟯 – 𝗦𝘆𝘀𝘁𝗲𝗺 𝗗𝗲𝘀𝗶𝗴𝗻 & 𝗣𝗿𝗼𝗷𝗲𝗰𝘁 𝗗𝗶𝘀𝗰𝘂𝘀𝘀𝗶𝗼𝗻
𝗗𝗲𝘀𝗶𝗴𝗻 𝗮 𝗠𝗘𝗥𝗡 𝗮𝗽𝗽𝗹𝗶𝗰𝗮𝘁𝗶𝗼𝗻 𝗳𝗼𝗿 𝗮 𝗿𝗲𝗮𝗹-𝘄𝗼𝗿𝗹𝗱 𝘂𝘀𝗲 𝗰𝗮𝘀𝗲.
• Food Delivery Application
• Learning Management System
• Job Portal Application
𝗣𝗿𝗼𝗱𝘂𝗰𝘁𝗶𝗼𝗻 𝗦𝗰𝗲𝗻𝗮𝗿𝗶𝗼𝘀
• Your Node.js server's CPU usage suddenly reaches 90%. How would you investigate?
• An API starts returning duplicate records. How would you identify and fix the issue?
• MongoDB memory usage keeps increasing in production. What would you investigate?
• A React application makes too many API calls. How would you debug and optimize it?
