trying to get node express app running

I have node, mongodb and redis installed on my machine (mac) and am trying to test this app https://github.com/vinkaga/node-backbone with the following instructions

Install and run MongoDB
Install and run Redis.io
Edit config.js if you are running MongoDB or Redis.io from another machine or non-default port
Start server by typing "node server.js"

Never having used node or express before and naively assuming that running node server.js would be enough to get everything started, I did it, but it said

![Error: Cannot find module 'express'][1]

This is the directory of the app

This is the package.json file. Is there something more that I have to do to get this running on a local machine?

{
    "name":"YOUR-PROJECT-NAME",
    "description":"YOUR PROJECT DESCRIPTION",
    "author":"YOUR NAME <your@emailaddress.com>",
    "version":"0.0.1",
    "dependencies":{
        "connect":">=2.1.2",
        "express":"2.x.x",
        "connect-redis" : ">=1.3.0",
        "jade":">=0.24.0",
        "ejs" : ">=0.7.1",
        "mongoose":">=2.5.14",
        "socket.io":">=0.9.5",
        "connect-assetmanager":">=0.0.27",
        "connect-assetmanager-handlers" : ">=0.0.18"
    },
    "devDependencies":{
        "vows":">=0.6.2",
        "mocha":">=1.0.1",
        "should":">=0.6.1",
        "request":">=2.9.x",
        "soda":">=0.2.5"
    },
    "engine":"node >= 0.6.12"
}