# Apache License 2.0, and effect on code we build

 JohnDallman Dec 16, 2014 at 3:52 PM Edited Dec 16, 2014 at 3:54 PM My employers' products are mathematical modelling libraries. These are written in C and C++, but we also produce wrappers for them written in C# so that they can be called from .NET programs. This works fine, and I'm not expecting Roslyn to cause us any technical problems. However, our legal department is very painstaking about intellectual property. That means that there's a formal approval process for all open-source code that we ship as part of the products, because some open source products have viral licenses, and therefore the lawyers want to be able to show that none of the open source we use does that. So I'm wondering if, when I build the .NET DLLs that we ship, if any kind of support or start-up code provided by the Roslyn project goes into them? My build command lines go like this, but all on one line, for VS.2013: csc /target:library /unsafe /noconfig /nostdlib+ /reference:"c:\Program Files(x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.5.1\mscorlib.dll" mainsourcefile.cs resourcesourcefile.cs /win32icon:iconfile.ico /keyfile:c:\path\to\keyfile.keys  That produces me mainsourcefile.dll, and works happily. I am not attempting to support any platform except Windows at present. I am using the tools that come with Visual Studio, rather than downloading and building my own, at present. So, will there be any code from the Roslyn project going into my DLLs? Does this depend on the using directives in the source? If there is any code incorporated, I'm going to have to track down the source for it all and get that approved for use, even though I'm not changing it. While open-sourcing .NET is a good thing for the world in general, it may be going to create some more work for me.