I wonder how the argument changes if you know you need an API for your mobile application that's almost identical in features to the web page. If you go the "R

I wonder how the argument changes if you know you need an API for your mobile application that's almost identical in features to the web page. If you go the "Rails/Django way" with server side rendered templates and, say, a bit of jQuery for fancy stuff -- you'll end up duplicating lots of code for the API (validation, routing, maybe even business logic). Anyone got experience with swapping your models/controllers for an API while keeping the rest of Django's/Rails' niceties? (authentication/sessions, Django's forms system, CSRF, etc.) OTOH having Django/Rails merely as a template system you probably could also go for very simple, self-contained client-rendered JS pages (e.g. .vue files). Not much difference there I guess?