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## Resource: About Service Plugins

## Article: About Service Plugins

## Article Link: https://dev.wix.com/docs/backend-extensions/service-plugins/about-service-plugins.md

## Article Content:

# About Service Plugins

A [service plugin](https://dev.wix.com/docs/overview/extensions-framework/backend-extensions/service-plugins.md) is a backend extension that Wix calls during one of its own flows, such as checkout or booking. This reference is the shared contract for that extension: the generated files, the configuration object, and the handler Wix calls.

A Studio Two site, a Wix CLI app, and a Wix-managed headless project each generate a configuration file and a handler. Studio Two imports the builder from `@wix/custom-extensions`. A Wix CLI app and a headless project import it from `@wix/astro/builders`. The handler calls `provideHandlers()` from the service plugin's SDK module. Self-managed apps declare the plugin in the app dashboard and expose their own endpoint instead of these files.

Which plugins exist, and which development path can add each one, is a fixed list. See [Available Service Plugins](https://dev.wix.com/docs/backend-extensions/service-plugins/available-service-plugins.md).

## What's in this reference

- [Service Plugin Extension Files and Code](https://dev.wix.com/docs/backend-extensions/service-plugins/service-plugin-extension-files-and-code.md): The generated file set, the configuration fields, and the handler.
- [Available Service Plugins](https://dev.wix.com/docs/backend-extensions/service-plugins/available-service-plugins.md): Every service plugin, the paths that expose it, and a link to its API reference introduction.

The API reference introduction for a plugin is the contract for that plugin's methods, including the request Wix sends and the response your handler must return.

## See also

- [Service Plugins](https://dev.wix.com/docs/overview/extensions-framework/backend-extensions/service-plugins.md)
- [Custom Business Logic](https://dev.wix.com/docs/overview/backend-services/custom-business-logic.md)
- [Service Plugin Extension Files and Code](https://dev.wix.com/docs/backend-extensions/service-plugins/service-plugin-extension-files-and-code.md)
- [Available Service Plugins](https://dev.wix.com/docs/backend-extensions/service-plugins/available-service-plugins.md)