Avalonia: Open Source Browsers & Extensions

What is Avalonia?

What it is

Avalonia is a cross-platform UI framework for .NET, written in C# and driven by XAML. It provides a flexible styling system and targets a wide range of platforms, including Windows, macOS, Linux, iOS, Android and WebAssembly. The project is mature and production ready, and it is used by companies such as Schneider Electric, Unity, JetBrains and GitHub. It lives in the .NET ecosystem and is distributed through the NuGet package manager.

The concrete problem Avalonia solves is cross-platform desktop and mobile UI for .NET developers who want a single XAML-based codebase instead of separate native stacks per operating system. It is widely considered the spiritual successor to WPF, offering a familiar, modern development experience for XAML developers. Avalonia is similar to WPF but is not a one-to-one copy, and it includes a number of improvements over that model. For teams that need to move existing WPF applications onto macOS and Linux, the project also offers Avalonia XPF, which runs WPF applications with little to no code changes.

Key capabilities

Cross-platform UI framework for .NET covering Windows, macOS, Linux, iOS, Android and WebAssembly.
Flexible styling system for XAML-based user interfaces.
XAML development model that is similar to WPF, with improvements over it.
Avalonia XPF, which runs WPF applications on macOS and Linux with little to no code changes.
NuGet packages for manual installation through the Package Manager console.
Tooling integrations for Visual Studio Code, Visual Studio 2022 and 2026, and JetBrains Rider.
MVVM support, as reflected in the project topics.

Who uses it and how

Companies such as Schneider Electric, Unity, JetBrains and GitHub use Avalonia in production.
XAML developers building cross-platform applications from a single .NET codebase.
Teams migrating existing WPF applications to macOS and Linux through Avalonia XPF.
Developers working in Visual Studio Code with the Avalonia for Code extension, which provides XAML previewing, code completion, diagnostics and code navigation.
Developers working in Visual Studio 2022 and 2026 with the Avalonia Visual Studio Extension, which provides project and control templates, a live XAML previewer, code completion and diagnostics.
Developers working in JetBrains Rider, where code completion, inspections and refactorings are supported out of the box, with XAML previewing available through the community-maintained AvaloniaRider plugin.

Getting started

Avalonia is delivered through the NuGet package manager, with packages available at nuget.org and manual installation performed through the Package Manager console using Install-Package Avalonia. The project also points to its Get Started guide, and offers editor extensions for Visual Studio Code, Visual Studio 2022 and 2026, and JetBrains Rider.

When to use it — and when not to

Avalonia is a strong fit for .NET teams that want one XAML codebase across desktop, mobile and WebAssembly targets, and it is a natural choice for WPF developers seeking a cross-platform path. Avalonia XPF is a commercial product licensed per-app, per-platform, so teams that need WPF compatibility on macOS and Linux should account for that licensing rather than treating it as part of the MIT-licensed core. The project carries a

project readme (upstream, from github) — read inline

License

📖 About

Avalonia is a cross-platform UI framework for dotnet, providing a flexible styling system and supporting a wide range of platforms such as Windows, macOS, Linux, iOS, Android and WebAssembly. Avalonia is mature and production ready and is used by companies, including Schneider Electric, Unity, JetBrains and GitHub.

Considered by many to be the spiritual successor to WPF, Avalonia UI provides a familiar, modern development experience for XAML developers creating cross-platform applications. While Avalonia UI is similar to WPF, it isn't a 1:1 copy, and you'll find plenty of improvements.

For those seeking a cross-platform WPF, we have created Avalonia XPF, enabling WPF applications to run on macOS and Linux with little to no code changes. Avalonia XPF is a commercial product and is licensed per-app, per-platform.

Blog

To see the latest announcements and read about the state of Avalonia, check out the Avalonia UI Blog.

Sponsorship

Avalonia development is supported by the generous sponsorship of Devolutions.

🚀 Getting Started

See our Get Started guide to begin developing apps with Avalonia UI.

Visual Studio Code

The Avalonia for Code extension gives you everything you need to build cross-platform .NET apps. XAML previewing, code completion, diagnostics, and code navigation, all inside the world's most popular editor. It's the fastest way to get started with Avalonia.

Visual Studio 2022 & 2026

The Avalonia Visual Studio Extension contains project and control templates, a live XAML previewer, code completion, and full diagnostics directly into Visual Studio.

JetBrains Rider

JetBrains Rider supports for Avalonia.

Code completion, inspections and refactorings are supported out of the box. To enable previewing XAML, you will require a 3rd party, community-maintained extension: https://plugins.jetbrains.com/plugins/dev/14839 to plugin repositories and install AvaloniaRider plugin.

Avalonia Packages

Avalonia is delivered via NuGet package manager. You can find the packages here: https://www.nuget.org/packages/Avalonia/

Use these commands in the Package Manager console to install Avalonia manually:

Install-Package Avalonia
Install-Package Avalonia.Desktop

Bleeding Edge Builds

We also have a nightly build which tracks the current state of master. Although these packages are less stable than the release on NuGet.org, you'll get all the latest features and bugfixes right away and many of our users actually prefer this feed!

Learning

Documentation

Documentation can be found at https://docs.avaloniaui.net.

Tutorials

We also have a tutorial over there for newcomers.

Samples

We have a range of samples to help you get started.

Breaking Changes

You can also see what breaking changes between Avalonia 11 and Avalonia 12.

Building and Using

See the build instructions here.

Contributing

This project exists thanks to all the people who contribute. Please read the contribution guidelines before submitting a pull request.

Code of Conduct

This project has adopted the code of conduct defined by the Contributor Covenant to clarify expected behavior in our community. For more information, see the Code of Conduct.

Security

If you discover a security vulnerability in any of our SDKs, tools, services, or repositories, please help us keep the community safe by reporting it responsibly.

You can report security vulnerabilities by emailing [email protected].

Please avoid disclosing the issue publicly until we have had a reasonable amount of time to investigate and release a patch or mitigation. We review all legitimate reports and will work with you to quickly resolve the issue.

Please note that Avalonia does not operate a bug bounty programme.

Licence

Avalonia is licenced under the MIT licence.

XPF - cross-platform WPF

Unleash the full potential of your existing WPF apps with our cross-platform UI framework, enabling WPF apps to run on macOS and Linux without requiring expensive and risky rewrites.

Frequently asked questions

Is Avalonia free to use?

Avalonia is open source under the MIT licence. There is no licence fee and no seat count — you can self-host it or, where the project offers one, pay a vendor for a managed version instead.

What does Avalonia do?

Develop Desktop, Embedded, Mobile and WebAssembly apps with C# and XAML. The future of .NET UI

What is Avalonia written in?

Avalonia is primarily written in C#. Its source is publicly available at https://github.com/AvaloniaUI/Avalonia, and it has 31,517 GitHub stars.