The Mono team is proud to bring you a preview of C# 5.0 a few years before our friends in Building 41 do. A snapshot of the code is available in the demo-repl.zip file. This contains the csharp.exe C# REPL shell and the Mono.CSharp.dll compiler-as-a-service assembly. With Today's code drop all those scenarios now work: Run Mono's C# compiler on .NET Embed Mono's Evaluator in your C# app. Use Mono'