Rivr is a traffic shaping library that sits on the server of mediation technology platforms such as SSPs and Ad Exchanges. Purpose built to improve the position of the programmatic supply side, Rivr's machine learning models makes recommendations that dynamically determine what bid and bidder match will yield the best outcome. The result is a streamlined programmatic trading system that works to enhance both efficiency (cost) and outcomes (revenue) of each auction, as well as the overall relationship between supply and demand.