YOE: 3 years
Interview Dates: April 2022

On site[Virtual]:

4 rounds

• 2 design
• 2 coding

Round 1:

• Design WhatsApp (or) any messaging service
  • Which protocol you will use and why?
    • Questions about HTTP vs HTTP Long Polling vs Web Sockets
  • How can we know the status of ssent/received/read
  • How do we know if online/offline?
  • Peer to peer Vs group chat

Round 2:

• Given a connected graph G=(V,E), give me the maximum number of eddges (both count and edges) which can be removed, so that the graph is still connected?

(Similar to https://leetcode.com/problems/redundant-connection/description/ )

Round 3:

• Given a directed graph. Print all the unique cycles in the graph.

Round 4:

• Design API Rate Limiter
  • How would you write an interface for this so ciients can consume?
  • In the implementation, what is the backend you would use?
    • No SQL Vs Redis

Standard behavioral questions related to microsoft principles, kind of 1 for each round and a few follow-ups on that.

Both the design rounds also had lot of questions on my resume (all related to work).

I was suprised, I got two design rounds. I expected at max 1 OOD but intervieweres were very friendly throughoout.