Separate backend from frontend

I think the backend should be completely separate from the frontend, and the frontend should interact with the backend through JS, with the backend returning JSON data instead of HTML... this allows anyone to make a custom frontend, and it makes the codebase cleaner... using this you can have an easier time implementing an account system, and other stuff that I cannot explain at the moment cuz it's 4 am. I may be happy to help, depending on the free time I have, but if I were the one doing the backend, I would probably do it in Express. (mainly because that's what I am more familiar with)