Event ticket purchase flow integrating React frontend, Redis caching, MySQL databases, and external payment gateways on AWS infrastructure. User authentication via MySQL, event browsing cached in Redis, and temporary ticket reservations locked in Redis before payment processing through Stripe or PayPal. Order confirmation triggers multi-channel notifications via WhatsApp Business API and email services, ensuring reliable end-to-end transaction management. Fork this diagram to customize payment providers, add queue services for async processing, or extend with analytics and fraud detection. The architecture demonstrates best practices for high-concurrency ticketing systems with cache-first reads and transactional writes.