Microsoft Open Sources XAML Studio: Reviving XAML Prototyping

Microsoft has officially open-sourced XAML Studio, a lightweight rapid prototyping tool for XAML-based UI development, under the .NET Foundation. The tool, originally released through the Microsoft Store as part of the Microsoft Garage initiative, now welcomes community contributions and collaboration via its GitHub repository. XAML Studio originated in 2017 during a hackathon, where the first prototype, dubbed ‘XamlPad+’ aimed to revive classic WPF-era tools like XamlPad, XamlPadX, and Kaxaml. Developed as a side project, it evolved over several years into a standalone app focused on WinUI and UWP prototyping. Until now, development was primarily internal, with partial components shared via the Windows Community Toolkit. The current open source release includes major updates targeted for version 2.0. These enhancements, housed in the dev branch, reflect significant UI redesigns based on Fluent principles, better integration with WinUI 3, and features such as live data context, property inspectors, and layout alignment tools. The new version also brings back features from the original prototype, such as folder support, which didn’t make it into the initial XAML Studio 1.0 release. Screenshot of XAML Studio v2 (in development) The move to open source marks a shift in how the tool is maintained and developed. As a seed project in the .NET Foundation, XAML Studio is now positioned for sustained community involvement. The announcement on GitHub acknowledges that the idea of open sourcing dates back to August 2017, but only now has the project reached a maturity level suitable for public development. While the current codebase is available, version 2.0 is not yet considered stable. Developers exploring the repository should be aware that some features are experimental and documentation is still evolving. Compatibility with legacy UWP workflows remains partial, and integration with Visual Studio is limited to external previewing rather than a full designer replacement. Still, the release is likely to benefit WinUI and XAML developers looking for a fast feedback loop without the overhead of full project scaffolding. It also sets the stage for further improvements by opening the door to contributions, issue tracking, and roadmap visibility.