Microsoft revealed today at its Build conference that Xamarin, the cross-platform application development framework it recently acquired, will be open-sourced and made part of the .Net framework.
"Everything you need to run Xamarin apps on any OS, any device, is now open source," Scott Guthrie, executive vice president of the Cloud and Enterprise Group at Microsoft, declared in the second day keynote at Build.
Xamarin for Visual Studio, the development application for Xamarin, is not being open-sourced, but Microsoft is doing the next best thing: It's offering Xamarin Studio for free to existing Visual Studio customers. Those running the Enterprise, Professional, or Community editions of Visual Studio will have access to Xamarin Studio as well.
For MSDN subscribers who use a Mac, a free Community Edition of Xamarin Studio will also hit shelves shortly.
Xamarin grew out of work done by developer Miguel de Icaza, whose Mono project attempted to port the .Net framework to platforms other than Windows. After Microsoft purchased the company, it seemed likely Xamarin products would be integrated with Microsoft's own line.
It's since become clear that Xamarin's work would eclipse Microsoft's efforts to create a cross-platform application development framework. The larger question was when (or if) its products would be rebranded as part of Microsoft's general offerings. Making Xamarin into a .Net project has the same effect. Xamarin may now be open source, but the fact that it's becoming part of .Net could have an even bigger influence on its future development.