Fullerite
Fullerite is a metrics collection system running on almost every machine at Yelp and (at the time of writing) powers most of Yelp’s system metrics. It started as an hackathon project to replace Diamond, because it was too resource hungry for the scale we were operating at. Now is a full-fledged drop in replacement for Diamond, supporting both Golang collectors and legacy Diamond collectors in Python.
The project is an on-going team effort and too many people worked on it to mention them, but it has been nice working on it all together. At the moment we do mostly maintainance and help people to write new collectors.