DIY monitoring solution. Every service had its own way of gathering metrics that were pushed into another home-made service where it could be fetched using a ha

DIY monitoring solution. Every service had its own way of gathering metrics that were pushed into another home-made service where it could be fetched using a half-assed query-language and rendered using, you guessed right, another home grown Javascript graphing library built with raw D3 calls. The whole thing required one full time guy just to keep it running and to tweak whenever someone needed to make a new dashboard using anything beyond the most basic queries. Just the graphing library alone would have been worth it to buy rather than develop ourselves. The rest, obviously Prometheus and Grafana are way easier to set up, integrates with other third tools and is much more powerful and battle proven than something developed from scratch, at no cost either.