OpenSilver, which is an open-source project designed to replace the defunct Microsoft Silverlight framework, has announced the availability of its new 2.1 release

According to the project’s maintainers, this update is a significant one for the platform. It adds support for F#, which is an open-source programming language that offers advantages that enable developers to write cleaner, more maintainable code and more robust applications. 

The maintainers explained that this addition allows developers to utilize the strengths of both XAML and F# togehter.

“The integration of F# into OpenSilver is a paradigm shift beyond mere language addition. The functional coding approach, coupled with XAML’s rich UI capabilities, can lead to faster development times, fewer bugs, and more readable code. For the .NET community, this represents an opportunity to explore new architectural patterns and potentially innovate in web application design,” the project maintainers wrote in a press release. 

Beyond the F# addition, the team also added more comprehensive coverage of the Silverlight Toolkit, adding many new UI controls like Rating, DomainUpDown, and GlobalCalendar. Additionally, the Toolkit allows developers to use Drag & Drop capabilities and includes 12 pre-made themes that are fully customizable. 

The team has also finished migrating the Silverlight Toolkit Samples app that was created by Microsoft, and it can now be accessed at

The next features that the team will be focusing on for future releases include adding a WYSIWYG XAML designer, enhanced WPF features support, and XAML Hot Reload