Microsoft is about to open source the Windows 11 user interface

Microsoft already has a lot of open source projects, and in recent years, the Redmond company has been more open to community contributions. However, there are still many 'important' parts of the code that are still being kept secret, including WinUI - the user interface framework of Windows 11. While not ready to 'open up' completely, Microsoft has just shared its plans for the next six months, which include product improvements and platform changes aimed at a more collaborative and transparent future.

Microsoft says that the process of open sourcing WinUI cannot be done in a 'click', because the framework is tightly coupled with many proprietary layers of the operating system that cannot be released in their original form. Therefore, the company needs time to separate out which parts can be shared publicly with the community, and which parts must remain private.

'Many people have asked about fully open-sourcing this project. While we can't commit to a specific timeline for completing the entire roadmap, the team is working towards it step by step. This isn't a 'one-and-done' thing, it's a deliberate process,' a Microsoft representative shared.

In addition, the development team must also prioritize other factors such as security, stability, and compatibility with existing products.

The WinUI open source plan will be implemented in stages:

Phase 1: Increase code sync frequency.
Soon after the release of WASDK 1.8 in late August, Microsoft will begin pushing internal updates to GitHub more frequently – to increase transparency and show the community the progress of the deployment.

Phase 2: Allow external developers to build the source code locally.
Third-party developers will be able to clone the code repository and build on their own machines, with documentation to help them set up and configure dependencies.

Phase 3: Support for contributions and testing.
The community can submit pull requests and run live tests. Microsoft is working on removing private dependencies and improving the testing system for public availability.

Phase 4: Shift development focus to GitHub.
GitHub will become the primary platform for development, issue tracking, and community interaction. Internal clones will be phased out.

The WinUI open source process will be a gradual one, and users can follow updates on the official GitHub tracking board. In the meantime, Microsoft encourages the community to contribute by submitting feedback, creating clear and quality issues, or voting on existing suggestions.

Samuel Daniel

Update 08 August 2025