We built a highly available EKS cluster for a fintech application, integrating autoscaling, metrics server, and external DNS. The setup included monitoring with Prometheus and Grafana, centralized logging with the EFK stack, and managed services such as RDS and Kafkaesque — all provisioned through Terraform. We also established a robust CI/CD pipeline using Jenkins and ArgoCD. The environment has been running seamlessly for over a year with zero downtime.