Event-driven microservices architecture on AWS combining CloudFront CDN, API Gateway, Lambda functions, and DynamoDB with integrated observability and cost tracking. User requests flow through CloudFront to S3-hosted frontend, then via API Gateway to Lambda functions that publish events to an event bus for asynchronous processing. Service discovery and sidecar patterns (Auth, X-Ray) enforce security and distributed tracing across the microservices layer. CloudWatch aggregates metrics and logs into dashboards while Cost Explorer tracks FinOps metrics from the event bus, enabling real-time visibility into performance and spending. This architecture demonstrates serverless best practices: decoupled services, event-driven communication, centralized observability, and cost optimization. Fork and customize this diagram on Diagrams.so to match your AWS account topology, add additional Lambda functions, or extend event consumers.