Design a Usage-Based Credit Tracking System for a SaaS Platform
Company: Clay
Role: Software Engineer
Category: System Design
Difficulty: medium
Interview Round: Technical Screen
Overview: This question evaluates a candidate's ability to design a distributed metering and billing system that tracks account balances, authorizes consumption, and prevents double-charging or negative balances under concurrent, bursty load. It tests system design skills around consistency, idempotency, and lifecycle management for usage-based billing, commonly asked to assess practical architecture experience with financial-grade data integrity.