The Mono Project (mono/mono) (‘original mono’) has been an important part of the .NET ecosystem since it was launched in 2001. Microsoft became the steward of the Mono Project when it acquired Xamarin in 2016.
The last major release of the Mono Project was in July 2019, with minor patch releases since that time. The last patch release was February 2024.
We are happy to announce that the WineHQ organization will be taking over as the stewards of the Mono Project upstream at wine-mono / Mono · GitLab (winehq.org). Source code in existing mono/mono and other repos will remain available, although repos may be archived. Binaries will remain available for up to four years.
Microsoft maintains a modern fork of Mono runtime in the dotnet/runtime repo and has been progressively moving workloads to that fork. That work is now complete, and we recommend that active Mono users and maintainers of Mono-based app frameworks migrate to .NET which includes work from this fork.
We want to recognize that the Mono Project was the first .NET implementation on Android, iOS, Linux, and other operating systems. The Mono Project was a trailblazer for the .NET platform across many operating systems. It helped make cross-platform .NET a reality and enabled .NET in many new places and we appreciate the work of those who came before us.
Thank you to all the Mono developers!
Contribute to the Project
Mono is an open source project and the code is available on GitHub. To contribute bug fixes or new features, just fork the repository and send us a pull request!
See the contributing guide for more information and an introduction into the development workflow.
We also regularly participate in Google's Summer of Code so if you're a student this might be a good opportunity for you.
Report Bugs
Whenever you encounter something that doesn't work as it should, we'd love it if you could open an issue on the Mono GitHub repo.
Make sure to include a detailed description of the issue and the steps needed for reproducing it. Attaching a small test case makes this even easier for us.
Get detailed instructions on how to file a good bug report in our bug reporting guide.
Get Help
We have several chat channels on Discord where our developers hang out regularly. See Chat for more information about connecting to our channels.
Feel free to file an issue on GitHub if you want to discuss something, even if it's not a bug.
Stack Overflow is a popular Q&A site where users can ask questions about software development, including Mono. Many Mono contributors and community members actively answer Stack Overflow questions tagged mono, so make sure your questions have the mono tag.