This small utility parses the output of passenger-status and produces values that can be used with the accompanying zabbix template (zabbix-template.xml).
Copy the binary to /usr/local/bin and put the userparameter_passenger.conf file to the correct location to be included in your agent configuration.
The helper binary looks for passenger-status in the path or a RVM wrapper for the default Ruby.
I am not a Go developer, so this code is pretty crude and probably not idiomatic Go.