Recurring debit/credit card payments via PayPal without PCI compliance...

Subscription management logic...

Requesting data from an API using Net::HTTP before a user logs in?...

Paypal recurring payments IPN confirmation...

Paypal recurring payments stopping...

Implementing our billing system in rails: Paypal, pure Merchant Account / Gateway, or something like...

Accepting recurring credit card payments for online software...

Recurring payments IPN...

Variable cost subscription payment provider UK...

What do I do about recurring billing?...

What are the associations between the models in a subscription/recurring billing Rails app?...

are automated recurring billings really automated?...

Recurring billing with Rails and ActiveMerchant: Best practices, pitfalls, gotchas?...

Retrieving ARB subscriptions with Authorize.Net API...