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## Resource: wix-payments

## Namespace: payment-provider

## Article: Introduction

## Article Link: https://dev.wix.com/docs/velo/events-service-plugins/payments/service-plugins/wix-payments/payment-provider/introduction.md

## Article Content:

# Introduction
The Payment Provider service plugin (formerly SPI) provides functionality for integrating your site with payment providers not currently supported by Wix.

With this service plugin, you can:
* Control the way your site connects to a payment provider.
* Handle transactions processed by a payment provider.
* Handle refunds processed by a payment provider.

Learn more about using the [Payment Provider service plugin](https://dev.wix.com/docs/develop-websites/articles/wix-apps/other-apps/wix-pay/payment-provider-custom-extension.md).

### To add a service plugin
1. [Add the plugin to your site](https://dev.wix.com/docs/develop-websites/articles/coding-with-velo/integrations/custom-extensions-spis/custom-app-extensions-using-sp-is.md#step-1-create-a-new-extension-on-your-wix-site).
2. Update the [`getConfig()`](https://dev.wix.com/docs/velo/events-service-plugins/payments/service-plugins/wix-payments/payment-provider/get-config.md) function in the **-config.js** file that is added to your site during step 1.
3. Update the [`connectAccount()`](https://www.wix.com/velo/reference/spis/wix-payments/payment-provider/connectaccount), [`createTransaction()`](https://www.wix.com/velo/reference/spis/wix-payments/payment-provider/createtransaction), and [`refundTransaction()`](https://www.wix.com/velo/reference/spis/wix-payments/payment-provider/refundtransaction) functions in the **.js** file that is added to your site during step 1.