Yes, that's why a lot of people who do SPAs also run node as the backend so that business logic code can be shared. If you have an e.g. C++ backend, you will ha

Yes, that's why a lot of people who do SPAs also run node as the backend so that business logic code can be shared. If you have an e.g. C++ backend, you will have to rewrite your models in JavaScript and keep them in sync. It makes your website have the same development tedium as a mobile app but without any of the prestige or profit potential. Avoid SPAs at all costs. More companies are starting to ditch them and only have websites as advertisements for the native mobile app (CashApp and Venmo off the top of my head).