Build a simple one page PHP script to generate random invoice make request to the AlphaCoins Payment API and return 1 on success https://www.alfacoins.com/developers
API - Application programming interface, IPN - Instant Payment Notification.
If you don't accept the variant with fixed amount payment button, then API+IPN will be glad to help any programmer. Payment, that valid for payment only 15 minutes, can be created by REST/JSON-RPC call. ALFAcoins send notification to merchant on status change for payment
php, ajax, curl
take and enjoy best service