Our new open source product went live this week: Modelus Specification. It is an implementation of a very powerful design pattern originally described in the Domain Driven Design book by Eric Evans as well as in this article by Eric Evans and Martin Fowler.
The library is written in C# using generic interfaces. The source code, binaries, and documentation are distributed under the Apache open source license, version 2.0.
Give Modelus Specification library a try and check out our other open-source products. Let me know what you think or if you have any questions. Enjoy!