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## Resource: wix-marketing-backend

## Namespace: events

## Article: Introduction

## Article Link: https://dev.wix.com/docs/velo/apis/wix-marketing-backend/events/introduction.md

## Article Content:

# Introduction
Wix  events are fired in your site's backend when certain events occur in your site's store.
 You can write event handlers that react to these events. Event handler functions
 receive data that corresponds to the event that has occurred. Use event handlers
 to create custom responses to marketing events.

 To add a marketing event handler, add an **events.js** file to the **Backend** section
 of your site if one does not already exist. All event handler functions for your
 site are defined in this file.

 Event handler functions are defined using the following pattern:

 ```javascript
 export function <wixAppName>_<eventName>(event) { }
 ```

 For example, an event handler that handles coupon creation in a Wix site looks
 like this:

 ```javascript
 export function wixMarketing_onCouponCreated(event) { }
 ```

 > **Note:** Backend events don't work when previewing your site.