Worked on the letsencrypt/boulder repository to enhance the robustness of Certificate Authority Authorization (CAA) tag parsing in backend systems. Addressed a bug by updating the Go-based codebase to recognize the 'issuevmc' and 'issuemail' tags, ensuring that the system no longer fails when encountering these tags in diverse CAA records. The solution involved implementing a recognition-only path for the 'issuevmc' tag, preserving existing behavior and minimizing risk to production flows. This backend development effort improved the reliability and compatibility of certificate issuance processes, reducing potential downtime and support incidents related to CAA parsing for dependent services.