Worked on the rabbitmq/rabbitmq-server repository to enhance the reliability of backend diagnostics by addressing a critical error handling issue. Focused on the Elixir-based status pathway, the work introduced nil-safe handling for the vm_memory_high_watermark metric, preventing crashes during maintenance or when the vm_memory_monitor is unavailable. By updating the status formatting logic, the solution ensured that missing values are reported as '(unknown)' rather than causing a FunctionClauseError, thereby improving error reporting and system stability. These changes, implemented in Elixir with a focus on robust backend development, were also cherry-picked to support Kolla-Ansible upgrade tasks and maintain operational continuity.