Can I send data via express next() function?

In this case you have a few options (only use one of these!):

1. You can just access the req.session.user.username variable from your my_tasks route
2. You can use res.locals
3. You can add data to the req object

In your exports.privateContent function, once a user is found in the database, you can simply add that data to the res.locals:

User.findOne( { 'username': username }, function ( err, obj ) {  if ( true ) {    // this variable will be available directly by the view    res.locals.user = obj;    // this will be added to the request object    req.user = obj;    next();  } else {    res.redirect('/');  }});

Then in your exports.my_tasks route, res.locals.user will be whatever obj was in the middleware. You can then simply access that in the view as the variable user.

So, all together, you can access the data in your route in these ways:

exports.my_tasks = function ( req, res ) {   res.render('tasks/tasks', {     userFromReq: req.user, // this exists because you added in the middleware     userFromSession: req.session.user, // this was already in the session, so you can access     userFromRes: [DO NOT NEED TO DO THIS] // because res.locals are sent straight to the view (Jade).   });};