How can I target .NET35 on OSX using mono and dnx/dnvm? - unity3d

Question

on Windows using Visual Studio 2015, I can compile a project with dnu build.
The project.json file looks as follows:
{
"version": "1.0.0-*",
"description": "My Class Library",
"authors": [ "Class Library template" ],
"tags": [""],
"projectUrl": "",
"licenseUrl": "",
"tooling": {
"defaultNamespace": "Common"
},
"frameworks": {
"dnx451": { },
"dnxcore50": {
"dependencies": {
"Microsoft.CSharp": "4.0.1-beta-*",
"System.Collections": "4.0.11-beta-*",
"System.Linq": "4.0.1-beta-*",
"System.Runtime": "4.0.21-beta-*",
"System.Threading": "4.0.11-beta-*"
}
}
}
}
After installing mono, dnvm and dnx on a Mac, as per this tutorial, I can actually compile the same project on OSX! This in itself is already pretty awesome!
now, I added the following framework to my project.json file:
"frameworks": {
"dnx35": { }, //"net35"
"dnx451": { },
"dnxcore50": {
"dependencies": {
"Microsoft.CSharp": "4.0.1-beta-*",
"System.Collections": "4.0.11-beta-*",
"System.Linq": "4.0.1-beta-*",
"System.Runtime": "4.0.21-beta-*",
"System.Threading": "4.0.11-beta-*"
}
}
This still compiles on Windows, and produces three sets of dlls, as expected.
However, on OSX it does not build the dnx20 target. Though as far as I understand, the mono compiler mcs can be set to target .net35 by passing in a sdk parameter.
So my question is: Can I target .NET35 with dnx on OSX using mono?
EDIT
The goal of this question is to compile a set of dll's that can be imported into Unity3d. And because Unity3d uses mono as a runtime, I would like to be able to do that by using dnu build, as to be able to develop these dll's on any platform.

Answer 1

You can pass custom Rosyln compiler options via compilationOptions in the project.json file:
"compilationOptions": {
"optimize": true,
"define": ["RELEASE", "TRACE", "PLAYSCRIPT"]
},
Take a look at the various project.json files in the Github aspnet/dnx project, i.e. project.json
But those options are being passed to Rosyln not mcs, Mono is being used as a CLR host for Rosyln's compiler as a service), but I do not believe you are substitute Mono's mcs for that (comments on this anyone?)