Observability and monitoring are essential for software teams. Given the unpredictable nature of certain events, creating accurate alert mechanisms with complex rules is crucial. However, the true validation of these rules comes only when scenarios arise in the wild. The unit testing for alerting rules technique allows teams to better define rules by proactively testing and refining them beforehand, increasing confidence in the way the rule is set up. This helps to reduce false alarms and ensure genuine issues are highlighted. Tools like Prometheus support unit testing for rules; our teams are already reporting its benefits in real-world settings.