OneTrust India Software Engineer Interview: Rounds, Questions and Preparation

What the job involves

A Software Engineer at a global product company like OneTrust India builds and maintains features for a cloud-based platform that helps organisations manage privacy, security, and compliance. Day to day you write clean code, fix bugs, review pull requests, and work with product managers and QA to ship reliable software. You also learn the codebase, debug issues in production, and contribute to design discussions.

Role and Technical Knowledge

1. 1

   Explain the difference between an array and a linked list, and when you would use each.

   Cover memory layout, access time, insertion and deletion costs, and give a practical example like a fixed-size buffer versus a dynamic queue.

2. 2

   What happens when you type a URL into a browser and press enter?

   Walk through DNS resolution, TCP handshake, HTTP request, server response, and rendering. Mention caching and HTTPS briefly.

3. 3

   Write a SQL query to find the second highest salary from an Employee table.

   Use a subquery with MAX or a window function like DENSE_RANK. Explain how you handle ties and nulls.

4. 4

   What is the difference between a process and a thread?

   Explain memory isolation, context switching, and shared resources. Give an example of when multithreading helps.

Practical Scenarios

1. 5

   You are assigned a bug where a user cannot log in after resetting their password. How do you debug it?

   Start by reproducing the issue, check logs, verify database updates, test edge cases like token expiry, and communicate findings clearly.

2. 6

   How would you design a simple URL shortener for a SaaS product?

   Discuss hashing, database schema, collision handling, and scaling reads. Mention caching and analytics if relevant.

3. 7

   Your code passes all tests locally but fails in production. What could be the reasons?

   Consider environment differences, configuration drift, data volume, network latency, and dependency versions. Suggest adding logging and staging checks.

4. 8

   You need to add a new feature to an existing codebase you have never seen. What is your approach?

   Explore the code structure, read documentation, find similar features, write a small prototype, and ask for a code review early.

Behavioural and HR

1. 9

   Tell me about a time you worked in a team to complete a project.

   Use the STAR method. Highlight your specific contribution, how you handled disagreements, and the final outcome.

2. 10

   Describe a situation where you had to learn something new quickly.

   Pick a real example from college or an internship. Explain the steps you took and what you achieved.

3. 11

   Why do you want to work as a Software Engineer at a product company like OneTrust India?

   Connect your interest in building scalable software to the company's domain, like privacy and compliance. Show you researched the product.

4. 12

   Where do you see yourself in three years?

   Focus on growing into a reliable engineer who owns modules and mentors juniors. Avoid vague answers like 'manager' without context.

Problem Solving and Coding

1. 13

   Given a string, find the first non-repeating character.

   Use a hash map to count frequencies, then iterate again to find the first with count one. Discuss time and space complexity.

2. 14

   Reverse a linked list iteratively and recursively.

   Explain pointer manipulation for iterative and base case plus recursion for recursive. Mention edge cases like empty list.

3. 15

   Check if a binary tree is a binary search tree.

   Use in-order traversal or pass min and max bounds. Clarify that a simple left-child comparison is not enough.

4. 16

   Find the missing number in an array of 1 to n.

   Use the sum formula or XOR. Compare both approaches and mention overflow risks with sum for large n.