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## Resource: About Service Plugins and Wix Functions

## Article: About Service Plugins and Wix Functions

## Article Link: https://dev.wix.com/docs/api-reference/business-management/functions/about-service-plugins-and-wix-functions.md

## Article Content:

# About Service Plugins and Wix Functions

[Service plugin extensions](https://dev.wix.com/docs/build-apps/develop-your-app/extensions/backend-extensions/service-plugins/about-service-plugin-extensions.md) are a set of APIs defined by Wix that you can use to enable your app to inject custom logic into existing business solution flows or to introduce entirely new flows to Wix sites.

Unlike traditional API endpoints where your app initiates a call with Wix, service plugins reverse the typical flow. Here, Wix calls your service during a specific flow, waits for your response, and then continues the flow based on your response.

Wix Functions act as service plugins. During a specific flow, Wix calls the function, waits for the function's response, and then continues the flow based on the function's response.

## Service plugin schema and configurations

Like service plugin extensions, functions often need static data to run. Static data refers to configuration values that don't change during the function's execution but determine how the function behaves.

For example, the `Checkout validations` function type requires a boolean value to determine whether the validations should show on the cart page. This boolean value is static data that gets passed to the function when it's called.

A function's service plugin configuration defines the static data that the function runs with. The function type that the function is based on defines what type of data the function needs in its service plugin schema.

## See also
- [About Wix Functions APIs](https://dev.wix.com/docs/api-reference/business-management/functions/about-wix-functions-apis.md)
- [Function Architecture](https://dev.wix.com/docs/api-reference/business-management/functions/function-architecture.md)
- [Function SPI Configuration API](https://dev.wix.com/docs/api-reference/business-management/functions/function-spi-configurations/introduction.md)