I would like to Develop a payment Gateway.
Am not sure of the best language to work on the API. can I use Phalcon Php together with C++.
What is the Best Approach?
Just only phalcon php and that's it. Also maybe incubator Phalcon\Http\Request\Client could be needed.
Developing payment gateway (PayPal, Stripe etc.) from scratch is not that simple, especially if you're asking questions on the forum. Don't get me wrong, but you have to realize the scale of such system first.
I also vote for Phalcon for sure - Micro app would be a perfect fit for such API, but you really need to plan carefully your system.
For HTTP client, all you need is a class wrapper over cURL lib such as this.
There is one built in in phalcon incubator - https://github.com/phalcon/incubator/tree/master/Library/Phalcon/Http/Client
I agree to all that. Every mile starts with a single step. The most important thing is good planning. And that is where I am.