Status: Tier 3 Non CS
Position: 5 years SDE at Product based company
Location: India
Date: Oct, 2021
Online Assessment:
https://leetcode.com/discuss/interview-question/1331054/PayPal-or-OA-or-SE-II-and-SE-III
After clearing Online Assessment, I was called for Onsite interviews in Oct 2021.(2 weeks after OA)
Round 1 - DS/Algo (Day1)
- Reorganize String - LC Medium
- Maximum Frequency Stack - LC Hard
I was aware of first question hence did quickly but not the second one. However interviewer was friendly and gave hints. Finally I was able to come up with stack based approach. Other than this, I was asked some project related questions.
Round 2 - System Design (Day1)
Design Chat service with deep dive into DB Schema, Read receipt, Caching, Multiple regions. Interviewer was highly interactive and drove the interview smoothly. Overall it was a very good interaction.
Round 3 - HM (Day3)
Behavioural questions like why leaving current company, discussions around projects and what the team I am getting interviewed for is working on. It was Paypal's core Payment processing team.
Round 4 - Technical Discussion (Day5)
This round was taken by architect of the team. I was expecting DS/Algo or Design question but it was completely different.
Questions
- CAP Theorem and how/when will you trade off Consistency and Availability and how to achieve tunable consistency.
- NoSQL vs SQL. When to use NoSQL over SQL, How NoSQL stores data when compared to SQL.
- REST API, OAuth and how TLS works.
- Caching and different levels of caching.
- Difference between Redis and Memcache. How redis achieves persistence.
- Project related Questions.
Verdict : Selected - Was requested for Documents 2 days after last interview.