title: Using passport.js to connect a local strategy to another (Facebook, Twitter, Google, etc)
body: <p>I have a node.js application which uses passport (with a modified passport-local for the login strategy) for authentication management. I would like to allow users to connect their social network accounts using passport strategies, but from what I can see the existing authentication (on the request object) gets overwritten when a new one is made.</p>
  
  <p>How should I approach this?</p>