Microsoft Open Sources .NET, Gets Cozier With Xamarin In Cross-Platform Lovefest

Microsoft took another big step toward getting its software running on more of the world's devices and platforms on Wednesday, releasing the server-side .NET stack to open source and unveiling a version of Visual Studio that lets developers build iOS and Android apps.

Microsoft said in April that it would open source certain elements of .NET, including ASP.NET and its .NET compiler platform, code-named Roslyn. In the coming months, it'll open source the rest of the .NET Core Runtime and .NET Core Framework, S. Somasegar, corporate vice president of Microsoft's Developer Division, said in a blog post.

"These projects will be released under the MIT open source license and we are also issuing an explicit patent promise to clarify users patent rights to .NET," Somasegar said.

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At the same time, Microsoft is also opening the door for developers to code .NET apps for Mac and Linux, Somasegar said.

Chris Hertz, CEO of Washington D.C.-based Microsoft partner New Signature, described open-sourcing .NET as a "huge move" that underscores the software giant's commitment to cross-platform development.

"This should in general deliver a better product more quickly, strengthening the value of .NET and the likelihood that developers will choose to build with .NET," Hertz told CRN.

Microsoft, in a press release outlining its plans, said it will work closely with the open source community and accept contributions for future improvements to .NET.

Xamarin, the vendor that runs the Mono open source .NET project, will be part of Microsoft's bid to bring .NET to Linux, Mac and other platforms.

Microsoft considered acquiring Xamarin earlier this year but ended up partnering with it instead, though the vendors' relationship has grown even tighter since then.

Miguel de Icaza, co-founder and CTO of Xamarin, described Microsoft's move as a "momentous occasion, and one that I have advocated for many years," in a blog post.

Rocky Lhotka, CTO of Magenic, a Minneapolis-based Microsoft development partner, told CRN he thinks Microsoft's open sourcing of .NET will help make Xamarin even stronger.

"This allows [Xamarin] to not only use .NET in a way they couldn't before, but to also contribute some of their code innovations in Mono into .NET itself -- mostly things around cross-platform support," Lhotka said.

Meanwhile, Microsoft also launched a preview of Visual Studio 2015, the coming update to its popular development tool, which includes support for iOS and Android for the first time.

Microsoft said it has worked with Xamarin to make it faster to install Xamarin in the coming Visual Studio release. Xamarin said it will add Visual Studio support in the free version of its product, called Xamarin Starter Edition, later this year.

To cap off the flurry of open source announcements, Microsoft also unveiled Visual Studio Community 2013, a free version of the product that developers can use to work with the Visual Studio core toolset.

Microsoft is committed to removing barriers to its software running on all kinds of devices and platforms, which has led to announcements that would have sounded like April Fools' jokes just a couple of years ago. By open sourcing .NET, Microsoft is showing once again that it's on a new track.

PUBLISHED NOV. 12, 2014