avalonia

Avalonia is an open-source, cross-platform UI framework for .NET that lets developers build desktop, embedded, mobile and WebAssembly applications using C# and XAML. It is often described as a spiritual successor to WPF, offering a familiar development experience for XAML developers while adding improvements and broader platform reach. Supported platforms include Windows, macOS, Linux, iOS, Android and WebAssembly. The framework provides a flexible styling system and is presented as mature and production ready, with listed users including Schneider Electric, Unity, JetBrains and GitHub. Tooling is available for several editors and IDEs. A Visual Studio Code extension provides XAML previewing, code completion, diagnostics and code navigation. Visual Studio 2022 and 2026 have an extension with project and control templates, a live XAML previewer, code completion and diagnostics. JetBrains Rider supports Avalonia out of the box for completion, inspections and refactorings, with a community-maintained plugin (AvaloniaRider) needed for XAML previewing. Avalonia is distributed through NuGet. The README shows installing the core package and the desktop package via the Package Manager console. Nightly builds tracking the master branch are also available for users who want the latest features and fixes sooner, though they are less stable than official releases. Learning resources include official documentation, a starter tutorial for newcomers, a separate samples repository, and notes on breaking changes between Avalonia 11 and Avalonia 12. Build instructions are kept in the repository documentation. The project welcomes contributions and asks contributors to read its contribution guidelines before submitting pull requests. It follows the Contributor Covenant code of conduct. Security vulnerabilities can be reported by email, and the project states it does not run a bug bounty programme. Avalonia is licensed under the MIT licence. A separate commercial product, Avalonia XPF, is offered for running existing WPF applications on macOS and Linux with little to no code changes. It is licensed per-app, per-platform.