Celigo Interviews

I interviewed for an SDE2/3 position at Celigo in Hyderabad, and the process consisted of three distinct rounds.

Round 1 - Data Structures & Algorithms

This round focused on my problem-solving skills. I was given the Unique Paths II problem from LeetCode. I initially solved it using a recursive approach within the allotted time. The interviewer then asked me to optimize my solution, which I proceeded to do.

Round 2 - System Design

The second round was dedicated to system design. I was tasked with designing a database schema for a platform similar to LinkedIn. This included discussing various queries and strategies to optimize their efficiency. Following that, I was asked to design a Job Scheduler from scratch and articulate how I would scale it to handle increasing loads. I managed to successfully address both problems and advanced to the next stage.

Round 3 - Technical Manager Round

The final round was with a Technical Manager. Here, the discussion revolved around my past projects, the challenges I encountered during their development, and how I overcame them. There were also several technical questions related to my specific tech stack, along with some behavioral questions to assess my fit.

I landed an interview opportunity with Celigo for a Senior Software Engineer position through a referral on LinkedIn. The entire process was structured into four distinct rounds.

Round 1: Data Structures & Algorithms

My first round involved tackling two medium-level data structures and algorithms questions. While I don't recall the exact problems, they were typical DSA challenges.

Round 2: Data Structures & Algorithms

The second round focused on a classic problem: implementing an LRU Cache. I was expected to demonstrate my understanding of data structures like hash maps and doubly linked lists to efficiently manage cache operations.

Round 3: Low-Level Design (LLD)

In the third round, the challenge was to design an elevator system at a low level. This involved detailing the components, their interactions, and the underlying logic to manage elevator movements and requests.

Round 4: System Design & Technical Discussion

The final round was comprehensive, starting with a system design problem to build a distributed counter. Beyond that, there were general high-level design questions, and a detailed discussion comparing PostgreSQL and MySQL, along with questions specifically about Kafka's architecture and use cases.

I successfully navigated all rounds and received a positive 'Hire' decision from Celigo.

Compensation & My Decision

Celigo extended an offer with a fixed salary of 44 LPA (including PF) and a joining bonus of 2 Lakh. After careful consideration, I decided to decline the offer as the compensation package was unfortunately equivalent to my current salary, providing no significant incentive for a switch.

A few months back, I saw an opening on LinkedIn and decided to take a chance — I sent a cold email to some of the engineering managers at Celigo, just out of curiosity and hope.

To my surprise, I got a response! About 3–4 days later, I received a call from HR, and that’s how the interview process began. And I’m super happy to share that I’ve now joined Celigo as a Software Engineer-2! 🤍

Here’s how the process went:

🔹 Round 1 – DSA (Online Coding Interview) The round started with a quick introduction and discussion about my current work experience. Then came the main part: a LeetCode medium-level DSA question. I hadn’t seen that one before, and honestly, I can’t recall the exact problem now 😅

I shared two different approaches and wrote the complete code during the call.

Result: Cleared ✅

🔹 Round 2 – Low-Level Design (LLD) This round also began with an intro and some project-related questions.

The main task was to design an LFU Cache, and the problem statement was clearly defined. I built the approach from scratch, and the interview turned into more of a collaborative discussion where we talked through design trade-offs and implementation details.

At the end, I was asked to write the code. I started, but couldn’t finish it due to time constraints.

Result: Cleared ✅

🔹 Round 3 – System Design + Managerial This was a mix of system design and managerial questions.

The interviewer asked me to explain the architecture of the product I currently work on. I opened up Draw.io and walked through each part of the system — why we use certain tools, how components communicate, and how the system scales.

We also discussed how we’d extend the system to support new features, which turned into a really engaging, deep product-level conversation.

Result: Cleared ✅

🔹 Round 4 – HR Round This round was mostly about my career journey, team culture, future goals, and a little bit of salary discussion. I had a great conversation with the HR head — very warm and clear.

Result: Cleared ✅

📨 Final Verdict I got a call for document submission right after the last round, and within a week — the offer letter arrived in my inbox! 🎉

What really stood out to me was how fast and smooth the entire process was. Interviews were scheduled back-to-back, and feedback came in almost immediately after each round. No unnecessary delays.

I’ve now officially joined Celigo, and I’m genuinely enjoying the remote-first culture and the people I work with .

Round 1

Coding: https://leetcode.com/problems/container-with-most-water/description/

Some questions based on my past experience.

Round 2

Thorough discussion on a project in my past experience.

Coding:

• A simple DS based question to answer few queries on O(1) time - Hashmap, heap
  • Follow-up to implement heap :) (I couldn't)
• https://leetcode.com/problems/best-time-to-buy-and-sell-stock-ii/description/ - slight variation on this
  • A follow-up using decreasing monotonic stack

Round 3

• Design and pseudo code: Given few files and the order for them, we need to copy (read + write) to a destination. We can parallelise the reads, but the writes to the destination should be in the exact order given. If F2 is after F1, we can read them, however we like but write F2 only after F1 is written.
  • Use threads to read, communicate between them using shared thread safe variable.
• Database and HLD discussion on order placing part of e-commerce like Amazon. How would you modify the system to support features like best selling books?

Round 4

Hiring manager: Typical questions on past experiences, questions on job switches, some leadership questions and discussion on the company and the role.