The Course Builder open source project is an experimental early step for us in the world of online education. It is a snapshot of an approach we found useful and an indication of our future direction. We hope to continue development along these lines, but we wanted to make this limited code base available now, to see what early adopters will do with it, and to explore the future of learning technology. We will be hosting a community building event in the upcoming months to help more people get started using this software. edX shares in the open source vision for online learning platforms, and Google and the edX team are in discussions about open standards and technology sharing for course platforms.