---
title: systemVersion
framework: foundation
role: symbol
role_heading: Instance Property
path: foundation/nscoder/systemversion
---

# systemVersion

The system version in effect for the archive.

## Declaration

```swift
var systemVersion: UInt32 { get }
```

## Discussion

Discussion During encoding, the current version. During decoding, the version that was in effect when the data was encoded. Subclasses that implement decoding must override this property to return the system version of the data being decoded.

## See Also

### Getting Version Information

- [version(forClassName:)](foundation/nscoder/version(forclassname:).md)