I tend to have a bitcoin payment gateway on my website. However, I cannot use any 3rd-party APIs out there. In fact, I have to build an application to do what those APIs do.
How can I do it?
I could not find a way to see how a bitcoin payment is processed. For instance, how can I detect if a payment has been done to print a invoice for the user? how the callback works and so on.
Any document or tutorial ?