Senior Software Engineer (Python) - Paypal
Summary
I interviewed with Paypal for a Senior Software Engineer (Python) role, which involved several technical rounds, system design, and two bar raiser interviews. Despite feeling confident after the latter rounds, I was ultimately rejected after a two-month-long process.
Full Experience
My interview journey with Paypal for the Senior Software Engineer (Python) role commenced with an online assessment on the Hackerrank platform, which included questions on SQL, DSA, and a machine coding style problem.
The first technical round, focused on Role Specialization, began with a brief discussion about my projects. This was followed by theoretical questions on Python, multithreading, and asynchronous programming. Subsequently, I was asked to solve a DSA problem, but due to time spent on theoretical questions, I could only pass a few test cases.
Next was the System Design round, where I was tasked with designing the Bookmyshow system, specifically focusing on ticket search and the payment process. Having prepared for this, I was able to successfully design and explain my approach within the allotted time.
The third round was dedicated to DSA. I was given two problems. For the first, I managed to write a brute force solution, which didn't pass all test cases, but I clearly explained my approach before moving on. The second problem was 'Remove All Adjacent Duplicates in String II'. I successfully solved this using a stack-based approach. With some time remaining, the interviewer presented a third problem which I don't clearly recall, but I was able to provide a brute force solution that passed most test cases.
The fourth round was a 'Bar Raiser' round. The interviewer seemed pressed for time, asking about my job change, technologies used in my projects, and engaging in project discussions. The interview concluded in about 20 minutes out of the scheduled 45. I later learned that this round didn't go well, which came as a surprise as I felt I had answered all questions satisfactorily and the interviewer appeared content at the time.
Following this, I had a fifth round, another 'Bar Raiser' with a different manager. This discussion felt much more positive. We started with my projects, then moved to situational behavioral questions, such as 'Tell me about a time where you had done something great apart from your work' and 'Tell me about a time where you had to learn something new & contributed.'
Eventually, after a prolonged two-month process, I was informed that Paypal decided to move forward with another candidate, without providing detailed feedback. I was quite shell-shocked by the rejection, especially after feeling confident about the second bar raiser round. I hope sharing this experience helps others.
Interview Questions (4)
Design the system for Bookmyshow, focusing on the search of tickets and the payment process.
You are given a string s and an integer k, a k-duplicate removal consists of choosing k adjacent and equal letters from s and removing them, causing the left and the right side of the deleted substring to concatenate. We repeatedly make k-duplicate removals on s until we can no longer do so.
Return the final string after all such duplicate removals have been made.
Tell me about a time where you had done something great apart from your work.
Tell me about a time where you had to learn something new & contributed.
Preparation Tips
For the system design round, I had prepared extensively beforehand, which proved beneficial. For Data Structures and Algorithms, my practice allowed me to come up with solutions, though not always optimal or fully passing. I also prepared for behavioral questions by reflecting on my past experiences and achievements.