I was having an issue where during the node-gyp rebuild process on my windows machine:

..\node-expat.cc(1): fatal error C1083: Cannot open include file: 'nan.h': No such file..

After running npm install nan --save I was still getting the issue, so I went into node-expat.cc and changed the include to be a relative path:

#include "node_modules/nan/nan.h"

Now everything is working fine.

It seems like this is more of an issue with node-gyp not updating the include_dirs in the build process on windows machines properly. Just wanted to make anyone who runs into this aware.