Disclaimer: I haven't read the article just yet. Saving it for later.
An alternative approach to this is to open vim with a blank .vimrc and add config as you need it. Nothing except what you REALLY need NOW to get things done. That's how I started my adventure with vim a few years ago and it's still paying off.
Which is what writing vim script essentially is. Or if vimscript is not enough, you can use literally any other language and integrate it via vimscript. I'm not an expert though but I have spent quite a lot of time on doing that.
I get that ViM is really powerful, so is Emacs and the like, however I'd guess a large part of going into the trouble of building your own text editor would be to learn about the algorithms and data structures used, something you can't do by writing ViM configuration files.
Well - not to be needlessly contrarian, but I've programmed that way (vim with nothing except what's included) for nearly 25 years now... it already has everything you need.
An alternative approach to this is to open vim with a blank .vimrc and add config as you need it. Nothing except what you REALLY need NOW to get things done. That's how I started my adventure with vim a few years ago and it's still paying off.