Back to Blog

How To Build PayPal From Scratch - System Design Series

How To Build PayPal From Scratch - System Design Series

Designing a global payments engine is one of the ultimate challenges in system architecture. As part of our System Design Series, I hosted a session on how to build a platform like PayPal from scratch.

Building payment systems requires precision and security. I walked through the system architecture, database schema designs, ledger management, and strategies for global scalability.

Key Takeaways:

  • Double-Entry Bookkeeping: Designing database schemas for reliable financial ledgers.
  • Transaction Concurrency: Managing locks and race conditions to avoid double-spending.
  • Global Availability: Structuring database replication and data storage across cloud zones.
  • Fraud Detection: Integrating real-time transaction screening models.

View the Presentation

Watch the full system design session on YouTube to see the architecture drawings and database schemas.