My first project at the tech book publisher O'Reilly was to build a git based multiformat publishing system with a great UI, from scratch, Atlas. When we started, there were just two of us in the new Brooklyn office, but by the end we had a great group of 6, working with the rest of the Tools Development R&D team spread out across the country.
Here are some of the features we supported:
It's still in use today, and it's grown to helping to power oreilly.com as well, as well as integrating with another project of mine, Thebe.
Additionally, I lead the development of a novel interactive video learning platform, powered by Thebe, and helped produce the video content for the pilot products, one of which featured Peter Norvig riffing on xkcd.
Later, as a contractor, I also worked on a system to give standardized assessments to students over the internet.
Our team took an interdisciplinary approach, so I worked on ux, design, front-end, and back-end to varying degrees for each of these projects.