Microsoft’s RIA Services are now open source and the code is available on Codeplex.

The codebase will be used in an Outercurve Foundation open source project which will be called Open RIA Services.

On the Open RIA Services .NET blog, Colin Blair said:

“As some people may already have noticed, the source code for Open RIA Services is available on the Codeplex site and as of today the project is officially open. I have populated the Issues list at Codeplex and almost everything on the issues list is currently listed as up for grabs.”

Colin Blair is a Microsoft MVP who is acting as the project leader for Open RIA Services. He says the team has a three-version roadmap, with the first version focused on bug fixes and minor features, and the next two major versions concentrating on more major changes including cross-platform clients.

RIA Services is a framework for building multiple tier applications for Rich Internet Applications (RIA). The problem with such applications is coordinating the application logic between the middle tier and the presentation tier. To create the best user experience, you want your RIA Services client to be aware of the application logic that resides on the server, but you do not want to develop and maintain the application logic on both the presentation tier and the middle tier. RIA Services solves this problem by providing framework components, tools, and services that make the application logic on the server available to the RIA Services client without requiring you to manually duplicate that programming logic.

The hope is that by making the project open source, the community will become involved in developing the system to make it easier to create cross-platform applications for the Web.  

The current version 4.3 targets Silverlight 5 as a client as did the original Microsoft library. Of course Silverlight is a dying platform and so the next version 5.0 is planned to be cross-platform.  In theory this will support .NET and WinRT including Windows Forms, WPF,  Mono and Mono for Android. It will also support JavaScript and move to a RESTful API.  Without being specifically tailored to a key Microsoft techology it is difficult to predict how useful the cross-platform version will be beyond being a lifeboat for Silverlight users.