Comment by chaps

Not OP, but one of the biggest issues that I've had with prometheus is that doesn't support the backfilling of timeseries data. Bringing it up to the prometheus devs led to oddly indignant responses that they had no intention of supporting backfilling, because that's not what prometheus was designed for. In large production systems, like prometheus is meant for, it was a very disappointing missing feature, and I could absolutely see why someone would want to fork if nothing else, just to get away from that level of indignancy.