Mux (https://mux.com/) collects performance metrics for video delivery & playback on the websites & apps of our customers. These metrics feed into our real-time alerting system. If the error-rate for a customer property (site) or video-title is exceptionally high then an alert will be triggered. Mux customers can configure alert notifications to be sent to Slack & email, and view a history of alerts in the Mux web dashboard. We also offer the ability to view breakdowns of playback failures, video start-up times, and more through our dashboard. This can be helpful for diagnosing playback issues related to specific browsers, geographies, ISPs, and more.