None. You can use C# as input language, compile it using CodeDom and run. The latter is a bit difficult as you need to do all in a separate Application Domain, but the ultimate value is: you don't use any 3rd part code and use available software which is compliant with ECMA and ISO standard.
Here is the skeleton of such application I depicted:
Create WPF Application that uses Reloadable Plugins...
code generating using CodeDom
]. This is just one file, you can copy and use if.
In both cases, the same idea: using the language (with run-time library) capable of compiling or interpreting code on the same language. In case of .NET, it can be any of standard .NET languages as well.