module.md

A Typical Module Layout

package.json
  {
    "main": "index.js"
    ...
  }
index.js
  var lib = require('lib');
  
  // do stuff with 
  // lib.apples
  // lib.bananas
  
  module.exports = {
    // dependency injection magic
  }
lib/
  index.js
    module.exports = {
      apples: require('apples'),
      bananas: require('bananas')
    }
  apples.js
  bananas.js

I think you mean require('./lib') in index.js there.