Christian Holl developed external TLS certificate support for the Jumpstarter controller and router in the jumpstarter-dev/jumpstarter repository, enabling users to provision their own certificates for enhanced security. He implemented a deployment mode that allows disabling ingress and route generation, providing greater configuration flexibility for enterprise environments. Using Python, YAML, Helm, and Kubernetes, Christian focused on backend development and gRPC integration to streamline certificate management and reduce operational friction. His work addressed the need for customizable security and deployment options, resulting in a more adaptable and secure deployment process. The feature was delivered within a month, demonstrating focused engineering depth.