[SciPy-user] Building Numpy with Visual Studio?

As I read the build guidelines for Numpy at www.scipy.org/Installing_SciPy/Windows I see that the instructions suggest that Numpy can be built with the MSVC tools against an ATLAS lib built with Cygwin tools. At this point I am perplexed. I thought that Cygwin used ELF and that Windows used COFF (actually PE) for static libs. So it is not obvious to me why setup.py should be able to build with the MSVC tools if the atlas and lapack libs are built with Cygwin tools. Maybe the Microsoft linker understands both ELF and COFF? Or maybe Cygwin actually uses PE? Can someone help me understand this? Thanks.