The full answer
PCI DSS is the security standard for any business that stores, processes or transmits payment card data. The simplest way to meet it is to avoid handling card data directly, so most of our designs use hosted payment fields, SDKs or redirects from established payment gateways.
With that approach, card details go straight from the customer's device to the payment provider, and your system stores only a token. That significantly reduces the requirements that apply to your own infrastructure.
Where a product needs deeper payment capability, such as a marketplace with split payments or a fintech app with stored cards, we design network segmentation, encryption, key management, strict access control and logging around the parts of the system in scope.
Your acquirer or payment provider determines which PCI DSS validation you need, such as a self-assessment questionnaire. We provide the technical documentation to support it and run vulnerability assessment and penetration testing before major releases.
Payment flows also need careful handling of failures and edge cases, such as declined cards, partial refunds, chargebacks and duplicate submissions. We design these explicitly and test them against the payment provider's sandbox before launch, so money and records stay consistent.