You can easily integrate your own custom payment gateway by emulating the API of another supported gateway. For example, you can expose the same transaction services (Authorize, Purchase, Capture, Void, Refund, etc.) from Authorize.net AIM developer guide and configure the Storefront to direct all calls to your gateway URL. The Storefront will process all payment transactions through your custom gateway. Your system will simply re-format the data and call your own custom payment gateway.
The Storefront currently supports a limited number of emulation endpoints from well known gateways like Authorize.net AIM, Authorize.net SIM, NMI, Princeton Card Connect. Please consult the API documentation of individual gateway for integration details.
Please contact us if you don't see the payment gateway you like to use.