NPM is just a no-way-going-to-work with prey and linux;
as i was saying it to the prey out-of-listening, through few subjects :
as neither on fedora or slitaz, more than one year we are expexting real support for a lightweigh prey for all plateforms in cmd line to avoid libs problems... we wont have, and i think never (maybbe in ten years) a such software working either on debian, slitaz,fedora or others arch/mint..
that's why i left prey few months ago... as i did when i saw prey for my ipod/ios5 was depreciated too...
dont wait, just forget!