And what watches the watchmen?

The microservices trend is great but this sort of monitoring starts to fall apart when you horizontally scale for HA. In this case we separate out our monitoring by doing synthetic requests at the service level, and then very specific health checking at the "instance" level (really containers now). Instance level health checks will ensure connectivity to outside dependencies, databases, filesystems etc. The trick is to know when a failure is a localized failure or a widespread failure. No sense in taking out all of the instances if they all can't talk to the DB.

Also, I'm not a Go developer but is this idiomatic?