Design a Visa-like payment processing system
Company: Databricks
Role: Software Engineer
Category: System Design
Difficulty: hard
Interview Round: Technical Screen
Overview: This question evaluates a candidate's ability to design a secure, low-latency card payment processing network, testing knowledge of distributed systems, transaction semantics (authorization, capture, refunds, reversals), idempotency, consistency and failure handling, data modeling, APIs, observability, fraud detection, and compliance.