---
title: "Shopper recognition"
url: "https://docs.adyen.com/point-of-sale/classic-library-deprecation/classic-library-integrations/shopper-recognition"
source_url: "https://docs.adyen.com/point-of-sale/classic-library-deprecation/classic-library-integrations/shopper-recognition.md"
canonical: "https://docs.adyen.com/point-of-sale/classic-library-deprecation/classic-library-integrations/shopper-recognition"
last_modified: "2026-05-24T12:54:31+02:00"
language: "en"
---

# Shopper recognition

[View source](/point-of-sale/classic-library-deprecation/classic-library-integrations/shopper-recognition.md)

We are [discontinuing classic libraries](/point-of-sale/classic-library-deprecation). If you are currently using a classic library, you need to migrate to [Terminal API](/point-of-sale/design-your-integration/terminal-api).\
Do not build a new integration with a classic library.

1. Initiate a transaction with the `GetAdditionalData` tender option, and without recurring parameters.

2. If a recurring contract already exists, the Adyen CA retrieves the `shopperReference` and `shopperEmail` from the recurring contracts based on the card number. The card alias is always returned.

3. The Merchant POS system is provided with these shopper details and can check the merchant database for previous shopper purchases. It can then decide on a discount for the ongoing transaction. 

4. The adjusted amount is then provided and the transaction can be completed. The merchant database can be checked on both shopper reference and card alias.