I wrote a prometheus library too: [https://github.com/dom96/prometheus](https://github.com/dom96/prometheus).
It features: * Counters, Gauges and Histogram support * Comes standard with a couple of useful collectors for tracking precisely where memory is being used in your program or which futures are waiting It is pretty simple, but has worked very well for my use cases so far. Example showing what the GC collector can generate: You can see the GC kicking in about midway through :)
