Windows App SDK
Stable release
1.2.3 / January 26, 2023; 3 months ago (2023-01-26)
Preview release
1.2.0 Preview 2 / October 5, 2022; 6 months ago (2022-10-05)
Operating systemWindows 10 version 1809, Windows 11
TypeApplication programming interface (API)
LicenseCreative Commons Attribution 4.0 International Edit this at Wikidata

Windows App SDK (formerly known as Project Reunion)[1] is a software development kit (SDK) from Microsoft that targets the development of native desktop applications on Windows 11 and Windows 10 back to version 1809.

Windows App SDK does not replace the Windows SDK; it is designed to enhance native Win32 (USER32/GDI32) and .NET 6 (WPF/WinForms) applications,[2] and migrate existing UWP apps to Win32 or .NET model[3][4] by providing a common application programming interface (API) based on UWP/WinRT and WinMD metadata, to bridge the gap between low-level system access in Win32 APIs and high-level programming concepts in .NET and UWP.[5][6] Version 1.0 has been released in November 2021 after several developer preview releases.[7][8][9]

Features and components

As of version 1.0, SDK components include WinUI 3, WebView 2,[10] MSIX-Core,[11] and C++/WinRT, Rust/WinRT[12] and C#/WinRT[13] language bindings. An API abstracting USER32/GDI32 primitives known as AppWindow was introduced to expose a unified set of windowing capabilities.[14] The feature roadmap for version 1.1 includes "modern windowing" in WinUI 3, supporting multiple client windows and custom window controls. Additionally, enhancements for power management, push notifications, and app restart are planned.

There are plans to add Win2D  to the Windows App SDK.[15]

See also


  1. ^ Ramel, David (June 24, 2021). "Windows 11 Development: Open Ecosystem Store, Project Reunion Rebrand and More". Visual Studio Magazine. Retrieved 2021-10-11.
  2. ^ Foley, Mary Jo (May 8, 2019). "Microsoft wants to close the UWP, Win32 divide with 'Windows Apps'". ZDNet. Retrieved 2022-01-13.
  3. ^ James, Allisa (October 19, 2021). "Microsoft is finally dropping UWP app support for Windows App SDK, here's why". TechRadar. Retrieved 2022-01-13.
  4. ^ Ramel, David (November 19, 2021). "Microsoft Says '.NET 5/6 Will Not Be Coming to UWP Project Types,' Developers Sound Off". Visual Studio Magazine. Retrieved 2022-01-13.
  5. ^ Anderson, Tim (November 29, 2021). "Project Union: Microsoft releases Windows App SDK 1.0, developers try to puzzle it out". The Register. Retrieved 2022-01-13.
  6. ^ "Overall migration strategy". Windows App SDK. Microsoft Docs. October 22, 2021. Retrieved 2022-01-13.
  7. ^ Foley, Mary Jo (November 16, 2021). "Microsoft's Windows App SDK 1.0 is available. Will it undo Microsoft's past mistakes?". ZDNet. Retrieved 2022-01-13.
  8. ^ Ramel, David (November 17, 2021). "Windows App SDK ('Project Reunion') Hits Version 1.0". Visual Studio Magazine. Retrieved 2022-01-13.
  9. ^ Ramel, David (October 11, 2021). "Windows App SDK ('Project Reunion') Polished Ahead of v1.0 GA Debut". Visual Studio Magazine. Retrieved 2021-10-11.
  10. ^ Foley, Mary Jo (May 19, 2021). "Microsoft continues to try to unify Win32, UWP Windows apps with 'Project Reunion'". ZDNet. Retrieved 2022-01-13.
  11. ^ "Msix SDK". GitHub. Retrieved 2022-04-19.
  12. ^ "Microsoft/Windows-rs". GitHub. Retrieved 2022-04-19.
  13. ^ "The C#/WinRT Language Projection". GitHub. Retrieved 2022-04-19.
  14. ^ "Discussion #370: Announcement: Proposed approach for windowing in Project Reunion". microsoft/WindowsAppSDK. GitHub. Retrieved 2022-04-19.
  15. ^ "Issue #1150: Proposal: Win2D Roadmap for the Windows App SDK". microsoft/WindowsAppSDK. GitHub. Retrieved 2022-04-19.