1st Round: Interview with Hiring Manager

• Ensured high-level technical fitness by asking questions about Microservices architecture, focusing on high availability, reliability, and scalability.
• Had a brief discussion about past companies, assignments, and challenges faced and overcome.
• Answered behavioral questions for a Technical Lead role, including conflict management with managers, peers, and customers.

2nd Round: Microservices Theoretical Questions and System Design (no coding)

• Began with theoretical questions on Microservices, covering topics like caching, circuit breakers, CQRS, the CAP theorem, and basics of authentication (JWT/OAuth).
• The next part focused on System Design:
  • Design a Facebook-like feature where a user can have multiple friends and see their latest posts upon logging in.
  • The system needs to handle millions of users, each posting hundreds of times per day.
  • Key considerations included designing a read-heavy system, potentially using CQRS, and interacting with granular microservices via message queues.
  • Eventual consistency was deemed acceptable, and strategies for handling post snapshots rather than real-time calculation were discussed.
  • Discussed key performance indicators (KPIs) for monitoring the system, with a hint towards message queue size for performance drop detection.

3rd Round: Coding

• Preferred languages were Java, Go, and C++, with openness to others.
• In 50 minutes, wrote a program to find the shortest path from a given node in a map to all other nodes.

4th Round: System Design

• This round offered two options: take-home assignment (submit within 2 working days, followed by a 1-2 hour in-person discussion) or a direct 5-6 hour in-person round.
• My problem statement involved designing an API to parse and analyze a file based on a given file ID, extract other file IDs from it, check their presence on disk, and return them.
• Included writing a small, working program for the core functionality.
• Discussed scaling the solution to a global level.
• Addressed deployment strategies for the solution.

I received another offer, so I did not complete the fourth round.