Multi-AZ XML record extraction and editing architecture leveraging AWS EC2, RDS PostgreSQL, Lambda, and ElastiCache for high-availability document processing. Web requests flow through CloudFront CDN and WAF to an Application Load Balancer distributing traffic across EC2 instances running PHP-based XML retrieval, DOM conversion, XSD validation, and XSLT transformation modules. PostgreSQL Primary in AZ-1 replicates to a Standby in AZ-2 for failover resilience, while ElastiCache caches XSD schemas and S3 stores schema definitions; asynchronous XML processing jobs queue through SQS to Lambda for background transformation. This architecture demonstrates enterprise-grade security, scalability, and fault tolerance for metadata-driven XML editing workflows serving external SRU endpoints. Fork this diagram on Diagrams.so to customize subnets, instance types, or add additional AWS services like API Gateway or DynamoDB. The design balances synchronous request handling with asynchronous batch processing, ideal for library systems, metadata repositories, or document management platforms.