Currently I am working at materials about creating Cross-Platform Render System. This materials entirely focused on architecture of Render System and how to create it from scratch. Material consist from several steps - each step add some feature set to base code.
Now material contain only source code. Articles will be ready soon.
Repository of material located at - https://github.com/ENgineE777/RS_Steps.
I hope that this material will be useful for anyone who want to create own game engine.