This service is developed by aeris.
Source code is available under AGPL v3 license :
This project contributes to improve Ruby too.
You can support development and hosting for this service:
Liberapay, for recurring donation, require a account (but respect your privacy)
Donorbox, for recurring and one-shot donation, doesn't require an account
Paypal, what to say about this service and your privacy, but already used by most of the world