Lago is an open-source Stripe Billing alternative.
This library will allow you to build an entire billing logic from scratch, even the most complex one. Lago is a real-time event-based library made for usage-based billing, subscription-based billing, and all the nuances of pricing in between.
The official Lago documentation is available here : https://doc.getlago.com
The contribution documentation is available here
Check the wiki guide
Lago is distributed under AGPL-3.0.