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/* Given an array of intervals where intervals[i] = [starti, endi], merge all overlapping intervals, and return an array of the non-overlapping intervals that cover all the intervals in the input. Example 1: Input: intervals = [[1,3],[8,10],[15,18],[2,6]] Output: [[1,6],[8,10],[15,18]] Explanation: Since intervals [1,3] and [2,6] overlap, merge them into [1,6]. Example 2: Input: intervals = [[1,4],[4,5]] Output: [[1,5]] Explanation: Intervals [1,4] and [4,5] are considered overlapping. */ ---------------------------------------------------------- Implement Jwt middlewear const jwt = require('jsonwebtoken') function authenticate(req, res, next) { jwt.verify(req.headers, (data) => { // data.user { } }) next() } function generateToken() { jwt.sign(userdata, algo, secret_key, (data) => { // token }) return token } ---------------------------------------------------------- //Suppose you need to build a scalable API for processing high-volume data uploads from multiple sources. How would you design the system using Node.js and PostgreSQL? let temp =fs.createReadStream() // temp.on('chunk', (chunk) => { // }) multer diskStorage -> middlewear ---------------------------------------------------------- Second highest salary SELECT MAX(salary) from salary where salary <> ( SELECT MAX(salary) from salary ) ---------------------------------------------------------- What is Closure, write code to demonstrate it Difference b/w var and let Is Nodejs single threaded ? How does it handle async operations ? Eventloop Promise vs Callbacks Challenges faced while converting from monolithic to microservices (data inconsistency) Questions on caching and redis In microservices if a single service goes down then how to deal with it ---------------------------------------------------------- Round 2 ---------------------------------------------------------- Questions on my past work, challenges faced, how did I tackle it, is there any better way to do it In a distributed system how to handle eventual data inconsistency Coding: create a node js app with 2 endpoints, 1 return straightforward response, other performs heavy calculations like fibonacci How to ensure performance and NodeJS's "non blocking" in such scenario
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Senior Backend Engineer

Interviewed at INTEGRTR

4.6★
Sep 21, 2025

/* Given an array of intervals where intervals[i] = [starti, endi], merge all overlapping intervals, and return an array of the non-overlapping intervals that cover all the intervals in the input. Example 1: Input: intervals = [[1,3],[8,10],[15,18],[2,6]] Output: [[1,6],[8,10],[15,18]] Explanation: Since intervals [1,3] and [2,6] overlap, merge them into [1,6]. Example 2: Input: intervals = [[1,4],[4,5]] Output: [[1,5]] Explanation: Intervals [1,4] and [4,5] are considered overlapping. */ ---------------------------------------------------------- Implement Jwt middlewear const jwt = require('jsonwebtoken') function authenticate(req, res, next) { jwt.verify(req.headers, (data) => { // data.user { } }) next() } function generateToken() { jwt.sign(userdata, algo, secret_key, (data) => { // token }) return token } ---------------------------------------------------------- //Suppose you need to build a scalable API for processing high-volume data uploads from multiple sources. How would you design the system using Node.js and PostgreSQL? let temp =fs.createReadStream() // temp.on('chunk', (chunk) => { // }) multer diskStorage -> middlewear ---------------------------------------------------------- Second highest salary SELECT MAX(salary) from salary where salary <> ( SELECT MAX(salary) from salary ) ---------------------------------------------------------- What is Closure, write code to demonstrate it Difference b/w var and let Is Nodejs single threaded ? How does it handle async operations ? Eventloop Promise vs Callbacks Challenges faced while converting from monolithic to microservices (data inconsistency) Questions on caching and redis In microservices if a single service goes down then how to deal with it ---------------------------------------------------------- Round 2 ---------------------------------------------------------- Questions on my past work, challenges faced, how did I tackle it, is there any better way to do it In a distributed system how to handle eventual data inconsistency Coding: create a node js app with 2 endpoints, 1 return straightforward response, other performs heavy calculations like fibonacci How to ensure performance and NodeJS's "non blocking" in such scenario

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