Zeta | SDE 2
Summary
I interviewed for an SDE 2 role at Zeta, navigating through four rounds covering DSA, technical concepts, system design, and behavioral questions. Despite receiving positive feedback, the position was reportedly filled.
Full Experience
I recently went through an interview process for an SDE 2 position at Zeta, which spanned four distinct rounds.
Round 1 – DSA
The first round focused on Data Structures and Algorithms. I was presented with two problems: Palindrome Partitioning II and Maximum Candies Allocated to K Children. I successfully solved both and advanced to the next stage.
Round 2 – Technical
This technical round delved into various AWS services and core computer science concepts. We discussed the distinctions between Redshift, RDS, and Athena, and explored the potential drawbacks of database partitioning. Other topics included AWS Lambda concurrency, a comparative analysis of EC2 versus Lambda, and key microservices concepts such as service discovery, retry mechanisms, and intermediate storage. We also had a detailed discussion comparing SQL and NoSQL databases, touching upon schema design, ACID properties, and scalability. Finally, I faced several Java trivia questions covering how to break the singleton pattern, polymorphism, the memory location of static variables, serialization, and stack memory.
Round 3 – System Design
For the system design round, I was tasked with designing a Service Discovery system within a 45-minute timeframe. The core requirements included registering and unregistering services, tracking all active instances, detecting and rerouting traffic from dead instances, and implementing load balancing. The follow-up questions probed into whether registration should occur at the service or instance level, how to handle new instance registration, mechanisms for gracefully removing dead instances, and how service dependencies discover each other.
Round 4 – Hiring Manager
The final round was with the Hiring Manager, which focused primarily on behavioral aspects. I was asked about handling conflicts with my manager and how I would support my manager in the event of team attrition. Towards the end, there was a Low-Level Design (LLD) problem to design an Airplane Reservation System that could manage multiple airlines and allow users dynamic selection. By this point, I felt quite exhausted.
Ultimately, HR conveyed that the feedback was positive, but the specific position I applied for had already been filled. They mentioned checking for other potential roles. My overall takeaway from the experience is that the company might not be genuinely hiring, and I'd be better off looking elsewhere.
Interview Questions (13)
You are given a 0-indexed integer array candies of length n representing the number of candies in each pile. You are also given an integer k. You are allowed to take a pile of candies and divide it into two or more smaller piles. The total number of candies in all piles remains the same. You cannot merge two piles into one. You want to allocate candies to k children such that each child gets the same number of candies, and that number is maximized. Note that each child must get at least one candy. Return the maximum number of candies each child can get. If it is impossible to allocate candies to k children, return 0.
Discuss the differences, use cases, and suitable scenarios for AWS Redshift, RDS, and Athena.
Explain why partitioning can be problematic in database or distributed systems, discussing its potential downsides and complexities.
Discuss AWS Lambda concurrency, how it works, its implications, and how to manage it effectively.
Compare AWS EC2 and AWS Lambda, highlighting their differences, use cases, advantages, and disadvantages.
Explain key microservice patterns and concepts including service discovery mechanisms, strategies for handling retries, and the role of intermediate storage in a distributed microservices architecture.
Discuss the fundamental differences between SQL and NoSQL databases, focusing on schema flexibility, ACID properties (or lack thereof), and scalability characteristics for each type.
Explain how to break the singleton pattern, illustrate polymorphism with examples, describe where static variables are stored in memory, discuss Java serialization, and detail the concept of stack memory in Java.
Design a Service Discovery system. Requirements:
- Register/unregister services
- Track all instances
- Detect dead ones, reroute traffic
- Load balance magically
Follow-up questions:
- Register at service or instance level?
- How to handle new instance?
- How to kill a dead one?
- How do dependencies discover each other?
Describe a situation where you had a conflict with your manager and how you resolved it.
If attrition happens within your team, how would you support your manager and the remaining team members?
Design an Airplane Reservation System with multiple airlines, allowing users to select dynamically.