We’re pleased to announce the release of the IronRuby CTP for .NET 4.0 RC. This is our third preview of IronRuby running under the Dynamic Language Runtime that is built directly into a .NET 4.0 release! As before, this release allows you to use IronRuby objects and types as .NET 4.0 dynamic objects from within C# and Visual Basic code. These binaries are equivalent to the functionality found in IronRuby 0.9.4. Please also note that the IronRuby CTP for .NET 4.0 RC will run only under .NET 4.0 RC.

For interop with IronPython, download IronPython 2.6.1 RC1 for .NET 4.0 RC

To try out this preview release:

• Install NET 4.0 RC or Visual Studio 2010 RC
• Download this release
• Follow any of the many dynamic walkthroughs online. This would be a good start

To build IronRuby for .NET 4.0 RC from source, get the sources from GitHub GitHub (direct download): use the "V4" build configurations.