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.
We also redesigned and rebuilt the content portion (i.e. not the store) of oreilly.com to run on Golang and look nicer.
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.