---
title: Configuration
framework: extensionfoundation
role: symbol
role_heading: Associated Type
path: extensionfoundation/appextension/configuration-swift.associatedtype
---

# Configuration

A type that manages configuration data for an app extension.

## Declaration

```swift
associatedtype Configuration : AppExtensionConfiguration
```

## Discussion

Discussion When you create a custom app extension, Swift infers this type from your implementation of the required configuration property.

## See Also

### Configuring the app extension

- [configuration](extensionfoundation/appextension/configuration-swift.property.md)