Multi-tier fintech payment platform on AWS af-south-1 with segregated Production and UAT VPCs, each spanning public, app, ops, and data subnets across availability zones. Traffic flows through Cloudflare and Internet Gateway to ALB, then to t3.large app servers backed by RDS MySQL 8.0.44 primary-standby pairs and ElastiCache Redis clusters for session and cache layers. Pritunl VPN servers, GoCD, Graylog, and Rundeck in private ops subnets enable secure administrative access and observability without exposing infrastructure to the internet. This architecture demonstrates defense-in-depth for payment systems: network isolation via VPCs and subnets, database high availability via multi-AZ RDS, caching via Redis replicas, and centralized logging via Graylog for compliance and incident response. Fork this diagram on Diagrams.so to customize CIDR ranges, instance types, or add additional regions for disaster recovery. Consider adding AWS WAF rules on the ALB and KMS encryption for RDS to strengthen payment card data protection.