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## Resource: About Event Extensions

## Article: About Event Extensions

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

## Article Content:

# About Event Extensions

An [event extension](https://dev.wix.com/docs/overview/extensions-framework/backend-extensions/event-extensions.md) is a backend extension that runs a handler when a Wix platform event fires. This reference is the shared contract for that extension: the generated files, the configuration object, and the handler that Wix calls.

A Studio Two site and a Wix CLI app each generate a configuration file and a handler. A Studio Two site imports the builder from `@wix/custom-extensions`. A Wix CLI app and a Wix-managed headless project import it from `@wix/astro/builders`.

## What's in this reference

- [Event Extension Files and Code](https://dev.wix.com/docs/backend-extensions/backend-events/event-extension-files-and-code.md): The generated file set, the configuration fields, and the handler.

The events themselves aren't listed here. Each event's page in the [API reference](https://dev.wix.com/docs/api-reference.md) gives its SDK method, its payload, and the permission scopes that let an app subscribe to it.

## See also

- [Event Extensions](https://dev.wix.com/docs/overview/extensions-framework/backend-extensions/event-extensions.md)
- [Events](https://dev.wix.com/docs/overview/backend-services/events.md)
- [Event Extension Files and Code](https://dev.wix.com/docs/backend-extensions/backend-events/event-extension-files-and-code.md)