I couldn't find very recent documentation, but the Blender wiki archive has a few articles that explain saving files. This article [1] in particular was an inte

I couldn't find very recent documentation, but the Blender wiki archive has a few articles that explain saving files. This article [1] in particular was an interesting read. It appears it is mostly a direct write of structs to disk. [1] https://archive.blender.org/wiki/index.php/Dev:Source/Architecture/File_Format/ https://archive.blender.org/wiki/index.php/Dev:Source/Archit...