Over the years I have been using content creation software which had a clear separation of a source and a rendered output. This has been LaTeX for scientific documents, Markdown and reStructuredText for computer documentation. I also use Markdown for my notes with Ghostwriter or Obsidian. I have also used GraphViz to create diagrams and graphs. To create 3D models I have used OpenSCAD, which is a programming language for 3D models. When I needed a Wiki, I have used DokuWiki All these software packages let me use the text editor of my choice, version the source code in Git and share it via GitHub. So for me, having a Git repository of Markdown files is the perfect way to create documentation.