Stuff I've written. All articles are licensed under a Creative Commons Attribution-NoDerivatives 4.0 International License.
The top level is a Go program that generates HTML from the articles using present. That program itself is licensed under a zlib license; the text thereof is at the top of ssg.go.
To add a new article, create a directory for it, then a .article file in that directory with the same name. E.g., an article called madoka needs ./madoka/madoka.article. Supporting files (images, source code, &c.) can just be placed in the same directory, I think. Once the article is written, add it to articles.json under an appropriate section. Lastly, go run . -out ../zephyrtronium.github.io -mf articles.json.
Also don't forget to open a GitHub Discussion when publishing a new article.