Although the parent didn't allude to it in his reply, the network effects that the npmjs registry provides is huge and is its killer feature. In my experience,

Although the parent didn't allude to it in his reply, the network effects that the npmjs registry provides is huge and is its killer feature. In my experience, there's usually multiple, specific modules for anything you're trying to do. Case in point, I'm developing a music curation service and there are no less than 5 recently updated modules for downloading from youtube and scores of them for converting playlists from one service to another.