Facebook Application Web Design/Graphic Design

My company developers Facebook applications in Ruby on Rails and is looking for a web designer to code our haml views and create our graphics. We provide all the application data - you do the view templates and css to spec. Hopefully, you create our app graphics as well. Most apps require minimal graphics - one large banner across the top of the screen (760px by ~150px) and one 16x16 icon. We're located in San Francisco but tend to keep late hours. We're pushing out a few apps per week and need a designer for the indefinite future.