During October 2025, Tianyu Zhou focused on enhancing CI/CD security across the aardvark-dns, netavark, and podman-machine-os repositories by implementing AWS credential rotation within their YAML-based configuration pipelines. Leveraging skills in AWS, DevOps, and security, Tianyu replaced encrypted credentials with newly rotated keys, ensuring compliance with security rotation policies while maintaining a strict no-functional-changes approach to production code. This work improved secret management practices and established an auditable change history, laying the groundwork for future automation of credential management. The depth of the changes reflects a methodical approach to hardening CI/CD environments without disrupting application behavior or stability.