Design an online ticket marketplace
Company: Walmart Labs
Role: Software Engineer
Category: System Design
Difficulty: medium
Interview Round: Technical Screen
Design a Ticketmaster-like system for discovering events and buying tickets.
Your design should cover:
- Functional requirements (e.g., browse/search events, view seating/sections, select seats or quantity, checkout, payment, confirmation, ticket delivery, cancellations/refunds).
- Non-functional requirements (e.g., high availability, low latency browsing, correctness under high contention for popular events, scalability for spikes/queueing, security/fraud prevention, observability).
- Data model (key entities and relationships).
- Core APIs (request/response shapes at a high level).
- High-level architecture diagram and key components.
- How you prevent overselling and handle concurrent seat purchases.
- Any tradeoffs (consistency vs availability) and failure handling.
Overview: This question evaluates system design and distributed systems skills, including scalability, high-availability architecture, concurrency control to prevent overselling, data modeling, API design, security and observability for an online ticket marketplace.
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