Stripe with custom form: Which data to submit to backend?

Hi,

I want to use s2member for the backend only, my registration page is completely customized, i do not want to use PRO forms.
I do know how to use the stripe javascript sdk, which data do i have to submit to which .php file (i noticed PRO forms submit to themselves) so s2member can create a subscription?

Thanks a lot :slight_smile: