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## Resource: Service Plugins

## Namespace: ecom-shipping-rates

## Article: Introduction

## Article Link: https://dev.wix.com/docs/velo/events-service-plugins/e-commerce/service-plugins/ecom-shipping-rates/introduction.md

## Article Content:

# Introduction
The Shipping Rates service plugin (formerly SPI) provides functionality for connecting your site to shipping rates providers not currently supported by Wix. You can also implement custom 
or external shipping rate options that don't come natively with Wix in your eCommerce purchase flows. These rates are displayed on your store's cart and checkout pages.
For example, you're not limited to how Wix apps, such as Wix Stores and Wix Bookings, define the number of shipping providers to choose from.

Wix eCommerce calls the service plugin endpoint [`getShippingRates()`](https://dev.wix.com/docs/velo/events-service-plugins/e-commerce/service-plugins/ecom-shipping-rates/get-shipping-rates.md) to retrieve the relevant shipping rates.

Learn more:
   + [Tutorial: Shipping Rates service plugin](https://support.wix.com/en/article/velo-tutorial-shipping-rates-custom-extension-beta)
   + [Velo: Custom App Extensions Using Service Plugins](https://support.wix.com/en/article/velo-custom-business-app-extensions-using-spis-beta)

### 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/e-commerce/service-plugins/ecom-shipping-rates/get-config.md) function in the **-config.js** file that is added to your site during step 1.
3. Update the [`getShippingRates()`](https://dev.wix.com/docs/velo/events-service-plugins/e-commerce/service-plugins/ecom-shipping-rates/get-shipping-rates.md) function in the **.js** file that is added to your site during step 1.