Payment System Design

This case study focuses on designing a payment platform that safely processes payments, handles retries, records ledger entries, reconciles transactions, and manages fraud controls.

What This Article Covers

• Scope and interview expectations
• Payment authorization, capture, refund, settlement, and reconciliation workflows
• Service boundaries for payment orchestration, ledger, risk, merchant, notification, and reporting services
• Idempotency keys, retries, duplicate prevention, and exactly-once business effects
• PCI considerations, tokenization, audit trails, and secure data handling
• Observability, incident response, and financial reconciliation

Learning Path

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