Round 1 – DSA

• Solving Questions With Brainpower
• Largest Divisible Subset

Result: Strong Hire

Round 2 – System Design (HLD + LLD)

Question: Design a Booking.com-style hotel reservation system.
Result: Strong Hire

Covered:

• High-Level Design (HLD): service boundaries, data flow, scaling strategies, component interactions (API Gateway, Search Service, Booking Service, Review Service, etc.)
• Low-Level Design (LLD): detailed class/data models, DB schema, API contracts, concurrency control for bookings

Key Requirements:

1. Search & Filtering (location, dates, price, ratings, amenities)
2. Availability & Booking
   • Real-time room availability, concurrency control to prevent double-booking
   • Booking creation, modification, cancellation
3. User Reviews & Ratings
4. Scalability & Reliability
   • Caching, load balancing, DB sharding by region
   • High-QPS handling during peak seasons
5. API Design & Data Model
   • Endpoints: /search, /book, /cancel, /reviews
   • Schema: Hotel, Room, Booking, User, Review tables

Round 3 – Hiring-Manager

This was the most difficult round in my opinion. The HM asked a mix of behavioral and past-experience-based questions, along with a couple of technical deep dives.

Questions which I couldn’t answer properly:

1. API Latency Debugging (without code changes):
   “Without adding new logs or deploying changes, how would you pinpoint whether high latency is due to DB access, business logic, or network?”

2. PATCH Endpoint Design:
   “How would you design a RESTful PATCH API for partial updates?”

   • The interviewer was specifically focused on JSON Patch semantics.
   • I was only familiar with JSON Merge Patch, which led to some confusion in articulating the request/response format.

Overall Result: Reject