PCI DSS Compliance Coding Guidelines

1. Overview

PCI DSS (Payment Card Industry Data Security Standard) is a set of security requirements established by the major card brands (Visa, Mastercard, Amex, Discover, JCB) to protect cardholder data wherever it is processed, stored, or transmitted. Every developer writing code that touches payment card information -- whether directly handling card numbers or integrating with a payment processor -- must understand these requirements because a single coding mistake (logging a full card number, storing a CVV, transmitting over HTTP) can cause a data breach, result in fines ranging from $5,000 to $100,000 per month, and revoke the organization's ability to accept card payments entirely.

2. The 12 Requirements (Developer View)