Worked on the zalando-incubator/kubernetes-on-aws repository to enhance the Fabric Gateway Custom Resource Definition (CRD), focusing on more flexible and precise traffic routing. Developed and integrated a HeaderRegexp predicate, enabling route matching based on regular expressions for request headers. Strengthened CRD validation logic to require at least one of headers or headerRegexps for each route, reducing the risk of misconfiguration and improving deployment safety. Leveraged Kubernetes CRD development skills and YAML to implement these changes, ensuring compatibility with existing deployments while expanding routing capabilities. The work addressed the need for advanced header-based routing without introducing breaking changes.