jade template engine greeting logged in user

I'm trying to understand how jade template engine works. I would like to open one of my .jade file fro开发者_开发技巧m the route in my node.js + express.js server passing some variable (for example if a user logs in, I would like to greet him). I know it's possible because I've been pointed to jade for that, but I can't find a good example on jade's github about that.

Does anyone of you already solved this and can help me? Thanks.

route:

app.get('/login', function(req, res){
   var usr = new User({username: 'myname'})   
   res.render('login/success', {
     title: 'Welcome',
     user: usr
   });
 });

login/success.jade:

h2 Welcome #{user.username}

or any number of other options. see https://github.com/visionmedia/jade for more help with the templating language.