Hello!
I can recommend ourselves haha
In
https://Quantox.com we have 300+ developers inhouse in 10 offices, 4 different countries and VERY adult experienced and very experienced with Payment Gateways (built few), including integrations into banks(did many), APIs, hosted payment pages, shopping carts, etc. Please email me at
[email protected] with your needs and let's go from there. Looking forward to hearing from you!