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## Resource: Extend the eCommerce Platform with Service Plugins

## Article: Extend the eCommerce Platform with Service Plugins

## Article Link: https://dev.wix.com/docs/api-reference/business-solutions/e-commerce/guides/extend-the-e-commerce-platform-with-service-plugins.md

## Article Content:

# Extend the eCommerce Platform with Service Plugins

Inject custom logic or integrate external services with the eCommerce platform using [service plugins](https://dev.wix.com/docs/build-apps/develop-your-app/extensions/backend-extensions/service-plugins/about-service-plugin-extensions.md).

For example, you can create a service that calculates custom shipping rates and seamlessly integrates them in a site's eCommerce flow.

Learn how to implement the following eCommerce service plugins:

| Extension | What you create | How you build it |
|-----|----|---|
| Catalog service plugin | Business logic for becoming a Wix catalog provider and integrating any external repository of sellable items with the Wix eCommerce platform. | [REST: Self-hosted app service plugin](https://dev.wix.com/docs/rest/business-solutions/e-commerce/service-plugins/catalog-service-plugin/introduction.md) / [Velo: Site service plugin](https://dev.wix.com/docs/velo/api-reference/wix-ecom-v2/service-plugins-spis/ecom-catalog/introduction.md) |
| Additional Fees service plugin | Business logic for calculating additional fees for a site visitor’s cart and checkout. | [SDK: Wix CLI or self-hosted app service plugin](https://dev.wix.com/docs/sdk/backend-modules/ecom/service-plugins/additional-fees/introduction.md) / [REST: Self-hosted app service plugin](https://dev.wix.com/docs/api-reference/business-solutions/e-commerce/extensions/additional-fees/additional-fees-service-plugin/introduction.md) / [Velo: Site service plugin](https://dev.wix.com/docs/velo/api-reference/wix-ecom-v2/service-plugins-spis/ecom-additional-fees/introduction.md) |
| Shipping Rates service plugin | Business logic for calculating shipping rates for a site visitor’s cart and checkout. | [SDK: Wix CLI or self-hosted app service plugin](https://dev.wix.com/docs/sdk/backend-modules/ecom/service-plugins/shipping-rates/introduction.md) / [REST: Self-hosted app service plugin](https://dev.wix.com/docs/api-reference/business-solutions/e-commerce/extensions/shipping-rates/shipping-rates-integration-service-plugin/introduction.md) / [Velo: Site service plugin](https://dev.wix.com/docs/velo/api-reference/wix-ecom-v2/service-plugins-spis/ecom-shipping-rates/introduction.md) |
| Discount Trigger service plugin | Business logic for applying discount rules to a site visitor’s cart and checkout. | [SDK: Wix CLI or self-hosted app service plugin](https://dev.wix.com/docs/sdk/backend-modules/ecom/service-plugins/custom-triggers/introduction.md) / [REST: Self-hosted app service plugin](https://dev.wix.com/docs/api-reference/business-solutions/e-commerce/extensions/discounts/custom-discount-triggers-integration-service-plugin/introduction.md) / [Velo: Site service plugin](https://dev.wix.com/docs/velo/api-reference/wix-ecom-v2/service-plugins-spis/ecom-custom-discount-triggers/introduction.md) |
| Payment Settings service plugin | Business logic to determine whether to apply 3D Secure validation during a merchant's payment process. | [SDK: Wix CLI or self-hosted app service plugin](https://dev.wix.com/docs/sdk/backend-modules/ecom/service-plugins/payment-settings/introduction.md) / [REST: Self-hosted app service plugin](https://dev.wix.com/docs/api-reference/business-solutions/e-commerce/payments/payment-settings/payment-settings-integration-service-plugin/introduction.md) / [Velo: Site service plugin](https://dev.wix.com/docs/velo/api-reference/wix-ecom-v2/service-plugins-spis/ecom-payment-settings/introduction.md) |
| Validations service plugin | Business logic for validating a site visitor’s cart and checkout. | [SDK: Wix CLI or self-hosted app service plugin](https://dev.wix.com/docs/sdk/backend-modules/ecom/service-plugins/validations/introduction.md) / [REST: Self-hosted app service plugin](https://dev.wix.com/docs/api-reference/business-solutions/e-commerce/extensions/validations/validations-integration-service-plugin/introduction.md) / [Velo: Site service plugin](https://dev.wix.com/docs/velo/api-reference/wix-ecom-v2/service-plugins-spis/ecom-validations/introduction.md) |
| Payment Provider service plugin | Business logic for integrating payments with Wix. | [REST: Self-hosted app service plugin](https://dev.wix.com/docs/api-reference/business-management/payments/payment-service-provider-service-plugin/introduction.md) |
| Tax Calculation service plugin | Business logic for calculating taxes. | [REST: Self-hosted app service plugin](https://dev.wix.com/docs/api-reference/business-solutions/e-commerce/extensions/tax/tax-calculation-integration-service-plugin/introduction.md) |
| Tax Groups service plugin | Business logic for managing default tax groups to categorize products from your app's catalog based on distinct tax treatments. | [REST: Self-hosted app service plugin](https://dev.wix.com/docs/api-reference/business-solutions/e-commerce/extensions/tax/tax-groups-integration-service-plugin/introduction.md) |

## Tutorials for site developers

If you are developing a site, check out these tutorials to learn how to implement a service plugin and expand your site's capabilities:

+ [Additional Fees Service Plugin Tutorial](https://dev.wix.com/docs/develop-websites/articles/code-tutorials/wix-e-commerce-stores/e-commerce-additional-fees-service-plugin.md)
+ [Catalog Service Plugin Tutorial](https://dev.wix.com/docs/develop-websites/articles/code-tutorials/wix-e-commerce-stores/e-commerce-catalog-service-plugin.md)
+ [Custom Discount Trigger Service Plugin Tutorial](https://dev.wix.com/docs/develop-websites/articles/code-tutorials/wix-e-commerce-stores/tutorial-custom-discount-trigger-service-plugin.md)
+ [Shipping Rates Service Plugin Tutorial](https://dev.wix.com/docs/develop-websites/articles/code-tutorials/wix-e-commerce-stores/e-commerce-shipping-rates-service-plugin.md)
+ [Validations Service Plugin Tutorial](https://dev.wix.com/docs/develop-websites/articles/code-tutorials/wix-e-commerce-stores/tutorial-validations-service-plugin.md)

## See also

+ Get started quickly with the [Custom Shipping Rates self-hosted app template](https://dev.wix.com/apps-templates/template?id=0580022b-625e-4467-9f78-28cc3e618483), which implements the Shipping Rates service plugin.
+ Follow this tutorial to [create a self-hosted custom shipping rates app](https://dev.wix.com/docs/build-apps/get-started/tutorials/tutorial-create-a-self-hosted-custom-shipping-rates-app.md) that implements the Shipping Rates service plugin.