Node.js Adserver for Mobile App

We'd like to add a custom ad server to our social networking mobile app. We're looking for a seasoned backend engineer, with experience in node.js to use this public GitHub ad server to deliver sponsored posts on our mobile app for a fee. Coder will have to implement the ad server, check out, allow users to purchases adds by click or impressions, show the ads by demographic data, and create relevant api's where needed.