Didn't know about this Handmade Seattle Conference until these recent links, but these OS demos have become my favorite posts on Hacker news. I'm sure most regular users saw the post, but there was one on SerenityOS that was also very cool.
Casey Muratori whose game project I think is the original inspiration for the Handmade community over the years also has streamed hundreds of hours of building a game entirely from scratch, I've learned quite a lot from them. https://www.youtube.com/playlist?list=PLnuhp3Xd9PYTt6svyQPyR...
great share, thank you!