github.com/pascaldekloe/metrics (go): Package metrics provides atomic measures and Prometheus exposition.  Counter, Integer, Real and Histogram are live representations of events. Value updates should be part of the respective implementation. Otherwise, use Sample for captures with a timestamp.  The Must functions deal with registration. Their use is intended for setup during application launch only. All metrics are permanent-the API offers no deletion by design.
Keywords: metrics|metrics-exporter|prometheus|prometheus-exporter