CoreBidder was released 2018-2019.
CoreBidder is a OpenRTB Demand-Side Platform written in C using Maxmind for GeoIP integration via libmaxminddb.
The bidder is extremely performant using minimal resources, the ustor-c version is USTOR 224 at the time the latest and most effective iteration; a bucketed hashmap using CRC64 and SHA1. No public release prior to publishing this repository was ever made for USTOR 224. The name was chosen because CRC64 is 64 bits and SHA1 is 160 bits thus 64+160 = 224 bits.
Video demonstration of the platform can be found here: