integration of a custom made third party payment gateway

[sums55]

Hi I have made a custom third party payment platform and I wanted to integrate it with Shopify so that merchants which are using Shopify can integrate my third party payment gateway to their websites. Basically I would like to add another third party payment gateway option to be a part of Shopify in addition to Paypal, stripe etc. What is the procedure to do this and is there anyone in Shopify I could contact with to discuss this further?