# Loyalty Card System Architecture

The loyalty card system is built on a flexible service architecture:

**SMS Verification Flow:**

* Optional SMS verification based on client configuration
* Session-based OTP storage for verification
* Resend capability for failed deliveries
* Configurable SMS gateway (console, external provider)

**Caching Strategy:**

* Loyalty points cached for 2 minutes per user
* Reduces load on external loyalty systems
* Automatic cache invalidation on updates