Extend a Banking Interface with Scheduled Payments and Account Merges

Company: Coinbase

Role: Software Engineer

Category: Software Engineering Fundamentals

Difficulty: hard

Interview Round: Technical Screen

Quick Answer: Design scheduled payments and account merging behind a stable banking interface. The discussion centers on deterministic execution order, idempotent requests, insufficient-funds behavior, atomic balance invariants, retired account identities, cancellation races, audit history, and crash-safe recovery.