Dream11 Interviews

Hello all, Recently completed all rounds of Dream11 SDE2. Sharing my experience.

Round 1 Coding

Duration: 1 hour

Questions:

1. https://leetcode.com/problems/minimum-number-of-arrows-to-burst-balloons/description
2. https://leetcode.com/problems/maximal-square/description/

Outcome: I was able to complete both the questions with optimal solution within expected time.

Verdict: Positive

Round 2 DB + HLD

Duration: 1.5 hours

Questions: DB - The interviewer wanted me to choose the DB that I have worked most with. I chose aerospike. He asked many questions related to the internals of aerospike (define aerospike fundamental terminologies, indexing, paritioning scheme, is a single node connection sufficient to reach the appropriate data, leader election). Apart from this, he asked questions on ACID properties. HLD - Design a job scheduler where clients can schedule one-time or recurring jobs and receive callbacks accordingly.

Outcome: I was able to answer almost all the DB related questions, expect one (I guess it was related to leader election in aerospike). Regarding the HLD design, I was able to provide a satisfactory solution. There was a little bit of to-and-fro through out the discussion though.

Verdict: Positive

Round 3 HM

Duration: 45 minutes

Questions: Explain one project that you have worked on. Tell me about one project that you found challenging and how did you solve it. Standard behavioral questions.

Verdict: Positive

Round 4 HR

Duration: 45 minutes

Questions: Standard HR level questions.

Verdict: Negative (I guess)

Two days after the final round, the HR called me and told "in your current org, you work in an environment where processes are streamlined. Our approach is a bit more chaotic here, so you may find it challenging."

The most bizzare reason I have ever heard for rejecting someone!

current exp: 4 years (MERN full stack) working with Product based company

Recruiter reached out to me directly on LinkedIn for the opportunity. He did basic screening and later reached out for Round 1.

Round 1: Problem Solving SDET came and straight away said that he will be sharing the 2 leetcode questions after introduction and i need to solve them in 1 hr. question 1: Sorted Array is given to you. In the array exactly 1 number appears more than 25% of the times. find the number solution: Gave O(n) solution. he wanted the O(log n). I tried a lot talked about lot of things around 25% & Binary search but didn't get the optimised solution. He asked me to write & run this solution only & gave an option to jump back once done with other question.

question 2: LinkedList is given to you. you have to reverse a specific section of the list. you'll get the start and end position for that section solution: took time (got confused while moving the references) but solved it. (it was expected to do in 1 pass and i did it)

Verdict: Cleared (recruiter reached out for Round 2 after a day). Overall interviewer was pretty chill and praised that i was talking out loud while typing the solution

Round 2: System Design & platform SDE 3 came (8-9 years experience). He discussed the problem and i was supposed to build the validation system. Question: dream11 team selection screen (more specifically validation System that will power the screen). Details:

• user will have certain credits
• he can select total 'X' number of players.
• can select max/min players in a specific category (ex: keeper, forward)
• can select max 'Y' players from a squad (i.e. Team)

My Retro inspection: It was my 1st time appearing for any kind of LLD round. I was extremely slow in the starting then tried to make it up but it was already too late. I even couldn't complete the "playerSelect()" method far from thinking of giving working solution.

I am yet to receive final rejection from recruiter. I will update here.

Initial Recruiter Call

After applying multiple times through various channels without success, I finally received a call from a recruiter within a week of my latest application. The recruiter provided valuable insights into the company, the team, and the desired skillset. We discussed my motivations for a change, my interest in the role, and my expectations. She outlined the interview process, which would consist of two online rounds followed by three onsite rounds. As I had been actively preparing and had recently completed a few other interviews, I was ready to proceed, and my first round was scheduled for the following week.

Interview Process

First Round: DSA Round

This round was a typical DSA interview where the interviewer immediately presented problems. I was given two LeetCode-style questions to code directly on the platform:

• Binary Search Variant: This question was similar to the Painter's Partition problem. I discussed my approach with the interviewer, who was satisfied, and then proceeded to code. I missed a couple of edge cases initially, but the interviewer guided me to correct them.
• Topological Sort Variant: This was a graph traversal problem that required topological sorting. I was able to solve it optimally on my first attempt.

By the end of this round, I felt confident about my performance, and the interviewer seemed satisfied. A few days later, the recruiter confirmed that I had cleared this round and would be moving forward.

Second Round: DB Design/Resume Round

I was initially told this round would focus on database design, possibly involving my past projects or a new problem statement. Despite getting stuck in Bengaluru traffic on my way to the office, I managed to start the interview on time. The round began with a deep dive into a service my team owned at Amazon. The discussion covered its architecture, latency, failure handling, scalability, multi-tenancy, monitoring, and various optimizations. Towards the end, the interviewer asked how I would build this service from scratch. Since I had already contemplated this scenario, I was able to articulate my ideas clearly.

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

Onsite Interviews

Dream11 conducts its onsite rounds in Mumbai. My interviews were scheduled a few weeks later, coinciding with the Diwali vacation, which gave me ample time to prepare for system design concepts. Dream11 provided all necessary transportation, including flights and cabs. On the interview day, I arrived in Mumbai in the early afternoon. The recruiter greeted me and offered lunch at their office, after which my three back-to-back onsite rounds began.

Third Round: System Design Round

This round was conducted by two SDE-3s and lasted over 90 minutes. The focus was on designing a real-time monitoring system, much like AWS CloudWatch or Prometheus combined with Grafana.

I began by gathering functional and non-functional requirements before moving on to the data model and overall system architecture. The interviewers introduced additional requirements as we progressed. I proposed a solution utilizing a Time Series Database, Kafka, and Apache Spark for real-time monitoring, although I later felt Flink might have been a better choice. We discussed scalability, failure handling, ingestion mechanisms, and various database choices. A significant portion of the discussion revolved around managing time windows for aggregation and metric ingestion. Towards the end, I was challenged to explain how I would implement a database from scratch using only EC2 instances. I detailed the architecture of MongoDB and Cassandra, covering aspects like append-on-file strategies, SSTables, bloom filters, merging, indexing, and replication strategies. However, I struggled to articulate search optimization techniques as I wasn't familiar with ElasticSearch and inverted indexing.

Despite struggling with a few questions, the in-person system design round was great for focused problem-solving. Later, the recruiter provided positive feedback, and I moved to the next round, which was a relief.

Fourth Round: Hiring Manager Round

This round was conducted by an AVP at Dream11. We started with a deep dive into the projects I had worked on. He asked me questions about system scalability, monitoring strategies, and on-call responsibilities. He also inquired about my day-to-day work, my role, and my responsibilities. Following this, he posed multiple behavioral questions, such as instances where I helped a teammate, how I handle multiple priorities, and my experiences with failures and subsequent learnings. Towards the end, we discussed Dream11's tech stack, ongoing projects, and their 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 point, I was quite exhausted from the travel and consecutive interviews. This HR round focused on culture fit and situational questions. I was asked about how I handle failures, manager feedback, and my motivations 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 a small amount of money. In hindsight, I realized I didn't structure my responses effectively using the STAR framework, and my answers lacked clear learning points, which may have impacted the outcome.

Post-Interview Experience

After about a week, I reached out to the recruiter for feedback, but she said she would get back to me. Despite multiple follow-ups, I received no response or rejection. Almost a month later, and after I had already secured another offer, the recruiter finally contacted me. She stated that my values didn't align with the company and mentioned some feedback from the system design round. She also mentioned conducting another debrief, but never reached out again.

Final Thoughts

Despite the outcome, it was a valuable learning experience.

I recently interviewed for the SDE-2 position at Dream11, and the process was thorough, with five rounds in total. The first two rounds were conducted virtually, and upon clearing them, I was invited to Dream11’s Mumbai office for the remaining three rounds. Dream11 took care of all travel arrangements, including flight tickets and cab transportation, making the experience smooth and well-organized.

Round 1: Data Structures and Algorithms (DSA)

This round focused on DSA concepts, where I was asked to solve 2 problems within a limited time (1 hour). The first problem involved using maps with string keys and list values, requiring a custom binary search implementation. The second problem asked me to remove k digits from a numeric string to form the smallest possible number. This was a straightforward DSA round, and the interviewers were supportive, providing helpful hints as needed.

Round 2: Database

The recruiter mentioned this round would focus on database concepts and a deep dive into my resume. The interviewer explored my past experiences, delved into my design choices, and thoroughly examined the tech stack I used in previous projects. They asked me to describe my current project, understand my design decisions, and justify my tech stack choices. There were also questions around PostgreSQL concurrency control, isolation levels, locks, replication, and how to scale PostgreSQL reads and writes. Some questions touched upon reactive stack, Netty, and R2DBC. I was also asked the classic question: how would I implement a BookMyShow ticket booking feature at scale, specifically how to ensure a selected seat is immediately unavailable to others. I have never experienced such an interview round; interviewers kept me on edge, and I felt they had the technical expertise to grill me hard if I messed up any questions.

Round 3: High-Level Design (HLD)

This was a high-level design round aimed at assessing my system design skills. The interviewer, a senior engineer, guided the discussion. I was tasked with designing an alerting and monitoring system similar to Prometheus and Grafana. The expectation was to first define the system's scope (NFRs and FRs), estimate scale and database storage, and discuss Consistency vs. Availability. We discussed how time-series data would be stored and in what format. Questions included how a Prometheus server would discover new pods for metric scraping and how to maintain active web connections with many clients simultaneously to scrape metrics. This was a fun round; discussions were mostly open-ended, and they were judging my ability to think about solutions and the pros and cons of each approach. Challenging questions were asked to assess my technical skills. Interviewers were also helpful if I got stuck on the problem statement.

Round 4: Hiring Manager

This round was taken by a Vice President who has been with Dream11 for over 8 years. Questions revolved around my previous work experience and certain scenario-based situations. I was asked how I would prepare my system for high-traffic events like the IPL, to explain the SDLC process I follow for feature development, and to describe the most challenging problem I solved at my previous company (Navi) and my contribution to it. They also asked how I keep myself updated with new technologies and the procedure I follow to solve incidents/bugs. He was a very humble person and wanted to understand my mindset and how I would handle challenging situations. This was roughly a 40-45 minute discussion, and no technical questions were asked.

Round 5: HR

This round was conducted by a very experienced HR professional. It included common questions, focusing on getting to know my background more personally. She asked about my childhood, schooling, college experiences, and how I developed an interest in coding. We also discussed my reasons for wanting to leave my current company and my perspective on my current colleagues. Additionally, she presented a few scenario-based questions to understand my approach in various situations, such as describing a time I went above and beyond to complete a task, what my manager would say about my strengths and weaknesses, and a situation where I failed but it proved to be a blessing in disguise. This was an overall fun round; we had a discussion for about 40-45 minutes, and she even told me about places I should visit in Mumbai before I left for Bangalore.

Two days after the interview, I received an email requesting documentation. I am currently in the salary negotiation phase.

I recently went through an interview process with Dream11, despite my initial reluctance due to the Mumbai job location. They managed to convince me to proceed, leading to a month-long process that eventually ended in a mutual reject.

The first step was a half-hour pre-screening call with the Head of Engineering.

Round 1: Machine Coding (System Design)
This round focused on system design, specifically requiring me to design a message broker system.

Round 2: Database Deep Dive
This round involved extensive questions about the databases I had used in my projects. Unfortunately, they weren't satisfied with my answers during this round.

Following these rounds, they offered to fly me to Mumbai for an onsite system design round, mentioning that only the flight expenses would be covered, with all other costs being my responsibility. The hiring manager round, if I were to proceed, would still be virtual. Based on this, I concluded it wasn't worth my time to continue.

I had my first round interview for the SDE2 role at Dream11. The interview focused on two coding questions. For the first problem, I initially provided a basic solution involving flattening the matrix and sorting, but the interviewer prompted me for a more optimized approach. After the interview, I realized a max-heap approach could solve it more efficiently. Unfortunately, I was unable to solve the second problem involving restoring IP addresses during the given time. Despite facing several rejections recently, I'm determined to keep practicing and improving.