I wrote a bit about the way I have implemented Stripe in my backend (running .NET) and the general structure I have followed. Find it here: https://corstianboerman.com/2020-08-14/a-blueprint-to-start-with-stripe-suscriptions.html
Even though I'm not quite happy yet about the structure it is something which works, and I'll try to solve that in the future again. If you happen to know about improvements upon the way I do things, please let me know!