In 2026 expect questions on process versus thread and when to use multithreading, reversing a string and a linked list with complexity, and networking basics like the OSI model or what happens when you type a URL and press enter. Interviewers reward structured, textbook-accurate answers and a correct small program. You do not need competitive-programming depth; you need to explain core CS concepts clearly and code a simple problem without stumbling on the basics.
01
Online aptitude and coding test
02
Technical interview on CS fundamentals and coding
03
HR interview on fit and flexibility
04
What to expect in each round
01
Round 1 (60-90 min)
online aptitude and coding test.
02
Round 2 (30-45 min)
technical round on OS, DBMS, networking, and a coding problem.
03
Round 3 (15-30 min)
HR round on motivation and mobility.
Technical questions HCL asked
Sourced from 2+ candidate post-mortems. Hit Practice to answer any one with AI voice feedback.
- 01
Medium
Reverse a linked list in O(1) extra space. Then explain when you'd use this in production.
- 02
Easy
What is the difference between a class and an object? Give an example.
- 03
Easy
Write a SQL query to find the second-highest salary in a department.
- 04
Easy
What is normalisation in databases? When would you de-normalise?
- 05
Easy
What's the difference between a stack and a queue? Give a real-world use case for each.
- 06
Hard
Given a stream of integers, design a data structure that returns the median in O(log n).
- 07
Medium
You have a service that's slow only on Tuesdays. Walk me through how you'd debug.
- 08
Hard
Here's 200 lines of payment-processing code with several intentional bugs. Find them and explain the production impact of each.
- 09
Medium
Explain webhooks vs. polling for a developer who has never built a payment integration. You have 4 sentences.
- 10
Hard
Walk me through Razorpay's fraud-detection model. How would you reduce false positives without increasing chargeback losses?
- 11
Medium
We see UPI failure rates spike at 9pm on weekends. How would you debug and what's your hypothesis?
- 12
Easy
What's 54% of 110? You have 10 seconds.