At work, we have a Prometheus metric from our build system named autobuild_build_timestamp that exports the timestamp for the latest build for a given application and Git branch. The process that exports this is stateless, so if it restarts or a new version of it is deployed, we're out of luck if we want to do something like build a dashboard to show the latest builds. One thing we can do is use a range query, but we can also make use of Prometheus' recording rules to provide a nice abstracti...