Simple subscription handling

A common use of Frisbii Billing & Pay Optimize is to have customers in the own system and customer subscriptions in Frisbii, where at any time a customer will have at most one active subscription.

This simple use case demonstrates how Frisbii can be used for signup, access control and subscription management without storing any data on the own system except the customer with a unique id. At some point, the solution could be extended to keep data on the own system for quick access. This could be done by synchronizing data between Frisbii and an own system using Webhooks.