Hey everyone. Hope all is well!

I recently had the opportunity to interview with Dream11 for an SDE-2 backend position. I had applied through the careers portal multiple times before without any response. I also tried reaching out to people for referrals and applied through different websites, but nothing seemed to work. This time, after applying again, I received a call from a recruiter.

Initial Recruiter Call
The recruiter reached out within a week of my application and provided insights into the company, the team they were hiring for, and the skillset they were looking for. She also asked me why I was looking for a change, what interested me in this role, and what my expectations were. After our discussion, she outlined the interview process, which consisted of two online rounds followed by three onsite rounds. Since I had been preparing for interviews and had already given a couple recently, I was ready to proceed. My first round was scheduled for the following week.

Interview Process 🚀

First Round: DSA Round
This was a typical DSA-based interview where the interviewer directly jumped into problem-solving. I was given two LeetCode-style questions and asked to code them on LeetCode itself.

• Binary Search Variant: This question was similar to Painter's Partition problem. I initially discussed my approach with the interviewer; he was satisfied and asked me to code. I missed a couple of edge cases, but the interviewer guided me to fix them. Similar Problem : LeetCode Link

• Topological Sort Variant: A graph traversal problem requiring topological sorting. I solved it optimally in the first go. Similar Problem: LeetCode Link

By the end of the round, I felt confident. The interviewer seemed satisfied, and after a few days, the recruiter informed me that I had cleared this round and would be moving forward. 😄

Second Round: DB Design/Resume Round
The recruiter initially told me this round would focus on database design, where I might be asked about my past projects or given a new problem statement.
I was planning to give this interview from the office, but while traveling there, I got stuck in Bengaluru traffic, as usual 😢. Fortunately, I managed to start on time. The round began with a deep dive into the service my team owned at Amazon. The discussion revolved around architecture, latency, failure handling, scalability, multi-tenancy, monitoring, and optimizations. Towards the end, the interviewer asked how I would build this service from scratch. Since I had already thought about this before, I was able to discuss my ideas clearly.

The discussion was engaging, and I was confident about my performance. A day later, the recruiter confirmed I had cleared this round and scheduled my onsite interviews.

Onsite Interviews
Dream11 conducts onsite rounds in Mumbai. My onsite rounds were scheduled after a few weeks due to Diwali vacation. They provided all the required transportation (cab, flight, etc.) to and fro. I got ample time to prepare for system design concepts and problems. On the interview day, I reached Mumbai at 1 PM. The recruiter greeted me and offered lunch at their office. Shortly after, my three back-to-back onsite rounds began.

Third Round: System Design Round
This round was conducted by two SDE-3s and focused on designing a real-time monitoring system, similar to CloudWatch or Prometheus with Grafana. This round went for over 90 mins.
I started by gathering functional and non-functional requirements before moving to the data model and system architecture. The interviewer added requirements as we progressed. I proposed a solution using Time Series Database, Kafka, and Apache Spark for real-time monitoring (though later, I felt Flink would have been a better choice). We discussed scalability, failure handling, ingestion mechanisms, and database choices. A major portion of the discussion revolved around handling time windows for aggregation and metric ingestion.
Towards the end, I was asked how I would implement a database from scratch using only EC2 instances. I explained MongoDB and Cassandra's architecture, covering append-on-file strategies, SSTables, bloom filters, merging, indexing, and replication strategies. However, I struggled to articulate search optimization techniques since I wasn't familiar with ElasticSearch and inverted indexing.

The in-person system design rounds were great for focusing on problem-solving. Though I struggled with a few questions, the recruiter later gave positive feedback, and I moved to the next round. I was relieved a bit. 😌

Fourth Round: Hiring Manager Round
This round was taken by an AVP at Dream11. We started discussion with projects I worked upon and deep dived into them. He asked me questions about system scalability, monitoring strategies, and on-call. He also asked about my day-to-day work, my role, and my responsibilities. Then he asked multiple behavioral questions, such as time when I helped a teammate, handling multiple priorities, facing failures and learnings, etc. Towards the end, we talked about Dream11's tech stack, ongoing projects, and work culture.

It was a productive discussion, and I was informed that I would proceed to the final HR round.

Fifth Round: HR Values Round
By this time, I was exhausted due to travel and back-to-back interviews. The HR round focused on culture fit and situational questions.
I was asked how I handle failures, manager feedback, and my motivation for joining Dream11. They also asked if I had played Dream11, to which I jokingly replied that I had played a Kabaddi match yesterday and lost my money (a small amount, though). 😁
In hindsight, I realized I didn't structure my responses well using the STAR framework. My answers lacked clear learning points, which may have affected the outcome.

Post-Interview Experience
I reached out to the recruiter for feedback after a week, but she said she'd get back to me. Despite multiple follow-ups, I received no response or rejection. After almost a month (I already had another offer), the recruiter contacted me, stating my values didn't align with the company and there was feedback from the system design round. She mentioned conducting another debrief but never reached out again. 😞

Final Thoughts
Despite the outcome, it was a great learning experience. Here are some key takeaways:

• Practice DSA: medium-hard level LeetCode problems.
• Practice System Design problems on whiteboard
• Prepare for Behavioral Rounds: Use STAR format to answer

I hope this helps others preparing for similar interviews.
happy Coding! 🚀