Previous Position - Software Engineer II
Previous Organisation - Sabre
Location - Bengaluru, India
Years of Experience - 1.5 years of Experience

Applied through referral.

Telephonic Conversation with HR (5-10 mins)

HR asked few questions about the current organization - CTC drawn, tech stack, reason for switch etc.
HR explained interview process - 3 Technical Rounds

Technical Round 1 - DSA
Technical Round 2 - Coding
Technical Round 3 - LLD

Technical Round-1 (DSA): (1 hr)

Interviewer was a SDE-2 with 3-4 YOE.

• We started discussing about my previous project for around 10 minutes.
• Then, jumped straight to problem solving.

Problem 1: https://www.geeksforgeeks.org/nth-node-from-the-end-of-a-linked-list/

• Explained 2 approaches of the problem.
• Coded the optimized solution in personal IDE.
• Then did a DRY run with the sample input and showed the output.
• He was satisfied with the solution.

Problem 2: https://leetcode.com/problems/longest-substring-without-repeating-characters/description/

• Explained him the naive approach first and then was asked to optimize it.
• Gave the optimized solution using hash maps and sliding window.
• Did a dry run first, then he asked to run sample test cases and all passed.

So, by then we were almost done with interview. He asked for any questions and concluded the interview.

Feedback : Positive. As I was able to solve all the problems. Got the call next day from HR that I made it for round 2.

I asked HR about the topic of discussion for the next round, but she said it could be anything around DSA, CS Fundamentals or System design etc. So, I was not sure about the discussion for the next round.

Technical Round 2(Coding): (1 hr)

When I joined the call, HR informed that Interviewer would be a bit late for conducting interview and she asked me to wait for 10-15 mins. After 15 mins, he joined the call and did apologize for being stuck with previous meeting.

We started with him giving his introduction. He was an engineering manager with 12 YOE and then he asked for my intro. He asked me about the topic which I would like to have discussion on. I said JAVA. Then he started with it.

JAVA and OOPS:

• What are four pillars of OOP? - I explained in details each pillar with example on my IDE.
• There was in depth discussion on every pillar with real life example. Recruiter was asking counter questions on my examples.
• Why String is Immutable in JAVA ? - I was not knowing about it, so I said that I know how to resolve immutability by using StringBuilder and StringBuffer class. But don't know exactly why it was made immutable.
• Interviewer was kind enough to tell me why it was immutable.

Design Pattern and Multithreading:

• Then he asked if I knew singleton design pattern and asked to implement it.
• Then he asked about some concepts related to multithreading and how to ensure that singleton class is thread safe.
• I explained about synchronized keyword and then he asked about double null check in it.
• We jumped on the design problem

System design and DB Schema:

• He asked me to give DB Schema for a food delivery app like swiggy/zomato by giving relevant details of the fields chosen.
• We had a discussion on it.

We almost finished time for interview - So, he concluded by asking if I had questions for him.

This was the best interviewer I had got till date. He was totally a chill dude and had conducted interview like if two friends were talking to each other. Didn't get a vibe of manager at all.

Feedback : Positive. Received the call next day from HR that I made it for the next round.

Technical Round 3(LLD): (1 hr)

Interviewer was again a manager with around 10 YOE.

• We started with his introduction first and then with mine.
• He was some one who worked in my previous organization so, had a 2-3 min chit chat on that.

Project discussion (10 mins) :

• He asked me to explain any of the project mentioned on my resume.
• I did that for around 10-15 mins. After that we jumped on the LLD question

System design :

• He asked me to design a payment app similar to Google pay with functionality of QR code payment, Bank transfer, Pay to contact and pay history.
• He said that I can use any online whiteboard portal to draw the components.
• I started with the requirements first and then moved to draw.io for the components.
• We had a long discussion on designing components and after that he jumped on to the DB
• He asked me to create whatever DB would be required for it.
• At last he asked SQL query related to my DB design. By then, we were done with the interview.

Feedback : Mixed. As Interviewer was expecting some of the components to be discussed in more details- like in pay history, what mechanism to you'll follow to store information in DB, API callback and time out etc. I was bit confused after this round.

I got the call from HR next day that I had made through all the rounds and have been selected.

Verdict : Selected