Worked on strengthening DNS resolution stability during a domain controller migration by updating Route 53 resolver target IPs within the ministryofjustice/modernisation-platform-environments repository. Leveraged AWS, Terraform, and HCL to align DNS configurations with new domain controllers, ensuring uninterrupted service for dependent systems. Validated FSMO role ownership to confirm a safe decommission plan for legacy servers, mitigating risks of DNS outages. The approach emphasized operational excellence by coordinating infrastructure changes with migration plans and real-time observations. This work focused on infrastructure as code practices, demonstrating careful risk management and attention to business continuity during critical platform transitions in a cloud environment.