we've been successful in deploying an EasyShop based shop within a
customer's website.

Yesterday the customer asked for "the missing Credit Card Security
Code (CVV) field" (i.e. the three digit code on the card's back side).

We're absolutely willing to implement that feature ourselves. The
question is, how to do that "the right way" (tm), circumventing
potential pitfalls.

I do understand, that I need to extend the ICreditCard Interface in
easyshop.core.interfaces.payment with a card_cvv TextLine.

1. Would that have any impact on anything besides the payment step in
the checkout process?

2. What else would I need to do?

Any pointers are highly appreciated.

TIA,

Andreas