RoR developer to add social networking++ to existing app by evanh

I am looking for someone to further develop an existing project of mine. I want to add a layer of social networking to the site. Users should be able to add friends and view their recent activities. Users will be rewarded through a point system for performing certain actions (ex… (Budget: $250-750, Jobs: CSS, HTML, MySQL, Ruby & Ruby on Rails, Social Networking)