My SDE-1 Backend Interview Experience at Zet (Previously OneCode)
Profile:

Experience: 1 year

College: Tier 3

Previous Company: Prominent Startup (Backend Engineer)

Applied via: Naukri.com

Status: Selected

📩 Application Process
I applied through Naukri.com, and within a few days, my resume was shortlisted. A recruiter from Zet reached out to me to initiate the interview process. The entire interview journey consisted of 5 rounds.

🧠 Round 1: DSA + Problem Solving (Online Coding Interview)
This was a live coding round that lasted about 60 minutes. The interviewer was focused on optimal solutions and clear communication.

Q1: Spiral Order Traversal of a Matrix

Q2: Group Anagrams

✅ I was able to solve both questions in about 35 minutes, with complete explanation of my approach, code, and time & space complexity.
📈 The interviewer appreciated the clarity and optimization of the solutions and gave strong positive feedback.

💻 Round 2: Technical + Low-Level Design
This round was a blend of core backend concepts, system design, and live coding, lasting about 75 minutes.

Questions:
What is Caching?

Types of caching (application, DB, distributed)

How did you implement caching in your current/previous role?

What is an LRU cache?

Live coding: Leetcode LRU Cache (implemented with HashMap + Doubly Linked List)

I wrote a complete working solution with correct logic and modularity. The interviewer was happy with my code structure and explanations.

Additional Concepts Discussed:
What is Context Switching?

Difference between Multiprocessing vs Multithreading

Processes vs Threads

💡 The interviewer gave positive feedback, and suggested brushing up on core subject knowledge (especially OS concepts) even more.

👨‍💼 Round 3: Hiring Manager Round
This round was primarily focused on my project experience, resume deep-dive, and behavioral evaluation.

Started with introductions

I was asked to walk through the architecture and flow of the main product I worked on

Discussion on tech decisions, scaling challenges, and team collaboration

Behavioral questions such as:

How do you handle tight deadlines?

A time when you disagreed with your team

What motivates you?

🎯 The feedback for this round was again positive, and the HM appreciated my ownership and clarity on my responsibilities.

🧍‍♂️ Round 4: HR Discussion
This was more of a cultural fit and motivations discussion.

Topics covered:

Walkthrough of my career journey

Why I’m looking for new opportunities

Why Zet?

Long-term career goals

Notice period and salary discussion

The conversation was smooth and professional, and helped ensure alignment with Zet’s vision and culture.

✅ Round 5: Hiring Manager Calibration Round
This was a short 15-minute final round, not technical in nature.

The HM used this round to:

Explain the role and responsibilities

Confirm expectations from both ends

Officially convey that the team was moving forward with my selection as an SDE-1 Backend Engineer