---
schema_version: "1"
id: eefbefec81c0e53cc070dcdca90a384b8355b29496e9fe469d85d0abf1c64b58
title: Create an Integration Definition
collection: developer
version: current
locale: en-us
portal_url: https://docs.salesforce.com/developer/current/en-us/industries-integrations/energy/guides/create-integration-definition.md
canonical_url: https://developer.salesforce.com/docs/industries/energy/guide/create-integration-definition.html
source_site: developer.salesforce.com
content_type: documentation
content_hash: 6499cd99bf1195c63806571598f1dfc320e4e79112a697c71b2b863fd4632845
products:
  - Energy and Utilities Cloud API
  - Industries Integrations
---
# Create an Integration Definition

To connect Salesforce with an external system, create Apex integration definitions. APIs work with the integration definitions to perform operations in both Salesforce and the external system.

Prerequisites

To use MuleSoft as the middleware layer, turn on MuleSoft Integration and create named credentials. See [Get Started with MuleSoft Direct Integrations](/docs/industries/energy/guide/Industry_integrations.html)

## Create an Apex Integration Definition

1. In Setup, in the Quick Find box, enter `Integration Definitions`, and then select **Integration Definitions**.
2. Click **New**.
3. For Type, select **Apex Defined**.
4. For Name and Developer Name, enter `EU_Integration`.
5. Click **Next**.
6. For **Apex Class**, search and select `eucommon.EUIntegrationHandler`.
7. Enter the attribute name.

   **note:** The EUIntegrationHandler Apex Class has the default named credential set to EU_Named_Credential. Replace the default value with the named credentials in your system.

8. Save the definition and then click **Activate**.