Prometheus is an open-source monitoring system that collects metrics from your hosts and applications, allowing you to visualize and alert on them. The syslog-ng Prometheus exporter allows you to export syslog-ng statistics, so that Prometheus can collect it. While an implementation in Go has been available for years on GitHub (for more information, see this blog entry), that solution uses the old syslog-ng statistics interface. And while that Go-based implementation still works, syslog-ng 4.