libdl issues with DUB

[Flamaros]

When I build our project with DUB under linux I get some link 
errors about libdl, that is messing.
In my main I have the following lines :

version(Posix)
{
    pragma(lib, "dl");
}
This works well with MonoD, so it seems like version Posix isn't 
defined with DUB or pragma ignored.