title: Can I run a private npm repository without replicating the public repository?
body: <p>I'm writing a number of pieces of code (for internal use) using node.js and want to store the modules (packaged up for npm) in a package repository for each distribution to the various machines they will be installed on.</p>
  
  <p>Ideally, I'd like a solution similar to Debian's apt repositories in which I can run a private repository server and configure npm to use a list of repositories to install from (When installing "foo", if "foo" is known by my private server install it from there, otherwise install it from the public server).</p>
  
  <p>However, it looks like the npm <code>registry</code> configuration key only accepts a single URL.</p>
  
  <p>Is there a way to achieve what I want?</p>
  
  <p>The closest I've been able to find have been:</p>
  
  <ul>
  <li>Mirroring the public repository locally and adding my packages on top of it… but I don't want to keep that amount of data (2.5G and still downloading) replicated on AWS.</li>
  <li>Hosting all my packages in git repositories and installing from there (which is more of a hassle).</li>
  <li>Hosting static packages on HTTP (as far as I can tell, this would prevent me from automatically getting "the latest version". I suppose I could do something with symlinks, but that is still less flexible than git, requires full URLs (which need to be kept up to date), and doesn't give a searchable repository.</li>
  </ul>