Wow, don't miss this deal if you have a SaaS product with subscription billing. You can integrate your billing using APIs and Webhooks (Webhooks only use the POST method). The API integration is well documented. The user interface is clean and intuitive, making it easy to navigate and set up. I had a support question and was pleasantly surprised to receive a response within 8 minutes. The team behind Rainex is highly responsive and eager to help, which is a huge plus. Overall, I am thrilled with my purchase and would highly recommend Rainex.