I was reached out by the recruiter, and the interview was scheduled for the next week. Enough time was given to me for preparation.

Total of 5 rounds were planned in advance, and I was told I would proceed to the next rounds if I cleared the previous rounds (eliminations).

First Round: General discussion on what I had worked on. No surprises.

Second Round: Practical coding questions, a mix of low-level and high-level system design. The interviewer gave clear instructions about what was expected in each task. This round went smoothly from my point of view.

Third Round: This was the round where things went upside down. The interviewer joined 30 minutes late and seemed uninterested. The interviewer did not follow basic etiquette. He spent 5-10 minutes reading my resume on the spot, with no communication and awkward silence.

The next 10-15 minutes followed with general questions about what I had worked on in the past.

Then I was given a puzzle question with certain constraints (no code required, a verbal solution was asked). I could not solve it optimally. Even the interviewer was confused, and he couldn't solve it with the constraints given.

(After the interview, I googled the solution for the same problem and came to know the constraints were a little different).

I got a call from the recruiter after 30 minutes that I was not selected and need not join for the next rounds.

TLDR: Difficulty-wise, I would say the interview was of medium difficulty. DSA - Leetcode easy and easy-medium. System Design - Practical questions, no surprises. Low-Level Design - Practical questions that most developers would have already worked on.

But a lot depends on the interviewer.

System Design: Design a distributed message queue.

Low Level Design: Design a rate limiter.

Coding: From two streams of very large numbers (not able to fit in int64 or float64), calculate the running sum and send the response over a third stream.

Puzzle: You have a set of 8 balls. 7 are of the same weight, and 1 is of a different weight (may be lighter or heavier). Find the odd weight ball in the minimum number of tries using a weighing scale.