I'm interested in privacy and security in Lightning Network. So most of my (private) repos are either papers that I plan to publish some day, or tools needed to do my research. Professionally I am a security engineer for Lightning Labs and contribute to their products such as LND and Taproot Assets.
I have two personal OS projects that I spend time on whenever I can. I have moved them under an organization, because hopefully at some time in the future loads of people will be contributing. The first project is Boilerplate Paper which is a tool for creating scientific papers, posters and slideshows in Markdown and convert them to different formats like LaTeX, Pdf, Word, PowerPoint or Html. The second project is a port of MetalSmith static site generator, called Janos, that runs entirely in the browser and is tightly integrated with Github and Github Pages so that it is hosted for free.
I post about my research and open source projects on my personal website at gijsvandam.nl which is (obviously) a Janos website itself.