During December 2024, Berger developed a feature for the kamailio/kamailio repository, focusing on enhancing observability in Kamailio deployments. He implemented a new xhttp_prom_tags parameter within the xhttp_prom module, allowing users to attach custom tags and labels to Prometheus metrics. This addition provided greater flexibility and granularity in metric reporting, enabling more detailed monitoring and operational insights. Berger ensured backward compatibility with existing Prometheus integrations while extending the system’s monitoring capabilities. The work involved system programming in C and leveraged expertise in Prometheus and monitoring practices, reflecting a focused and technically sound approach to improving metric customization.