# Windows build path changed to add the target architecture

> In preparation for supporting Windows on Arm64, the Windows build path was updated to include the target architecture.




:::important
These breaking change docs are accurate, as of the release
under which they are published. Over time, the
workarounds described here might become inaccurate.
We don't, in general, keep these breaking change docs up
to date as of each release.

The [breaking change index file](/release/breaking-changes)
lists the docs created for each release.
:::


## Summary

Built executables for Flutter Windows apps are now located in architecture
dependent folders.

## Context

In preparation for supporting Windows on Arm64, the Windows build path was
updated to add the build's target architecture.

Previously, Flutter builds for Windows assumed an x64 target architecture.

## Migration guide

You may need to update your infrastructure to use the new Flutter Windows
build path.

Example build path before the migration:

```plaintext
build\windows\runner\Release\hello_world.exe
```

Example build path after the migration if targeting x64:

```plaintext
build\windows\x64\runner\Release\hello_world.exe
```

Example build path after the migration if targeting Arm64:

```plaintext
build\windows\arm64\runner\Release\hello_world.exe
```

If you use [`package:msix`][], update to version 3.16.7 or newer.

[`package:msix`]: https://pub.dev/packages/msix

## Timeline

Landed in version: 3.15.0-0.0.pre<br>
In stable release: 3.16

## References

Design document:

* [flutter.dev/go/windows-arm64][]

Relevant pull requests:

* [Introduce architecture subdirectory for Windows build][]

[flutter.dev/go/windows-arm64]: https://flutter.dev/go/windows-arm64
[Introduce architecture subdirectory for Windows build]: https://github.com/flutter/flutter/pull/131843