Microsoft Shifts WinUI Development to GitHub

Microsoft has taken another significant step in its effort to revitalize and modernize its Windows developer technologies. The company has moved development of WinUI (formerly known as WinUI 3) and the Windows App SDK (WASDK) to GitHub, a move that marks the fourth phase of a plan announced last August.

The move is designed to make maintenance and updates more open and collaborative with the community. However, it's worth noting that Microsoft has not yet opened up the codebase to contributions from outside developers. That will come after the company has proven that this development system is working effectively.

A Microsoft engineer explained the change in a statement: 'Mainline WinUI development is now taking place on GitHub.' This means that WinUI engineers and other Microsoft developers are creating branches, opening pull requests, reviewing, validating, and merging changes right there on the GitHub repository. The company's day-to-day engineering work is now happening in the open, allowing users to follow progress as it happens.

This move follows a broader push by Microsoft to address 'pain points' in Windows 11, which was announced at Build 2026 back in May. The ultimate goal of this effort is to make WinUI fully open source, following the model established with legacy Windows developer frameworks like Windows Presentation Foundation, Windows Forms, and the Windows UI XAML Library.