I will start, but feel free to argue my point. To me, compliance and risk is my biggest challenge when it comes to coding for payments. Yeah i know, this is probably everyones biggest challenge. I data, but when it comes to other peoples data my palms start to sweat a little.
I would say security. You never know when you can be a victim to malicious attacks. New methods are devised every day and it’s getting hard to catch up.