Get an API for free with Blend. After calling the middleware just call res.blend()

blend.js

var _blend = function(req, res, next) {
  res.blend = function(params) {
        params.buildData(params.params, function(e, d) {
            if(req.headers['content-type'] === 'application-json') {
                    res.json(d);
            } else {  // render html
                params.buildSelectors(d, function(selectors) {
                    
                    if(req.headers['content-type'] === 'sizlate') {
                        var options = {
                            layout: (req.param('_frax')) ? null : params.layout,
                            container: params.container || '#container',
                            selectors: selectors
                        };
                        res.json({
                            template: params.template,
                            selectors: options
                        });

                    }else {
                        res.render(params.template, options);
                    }
                });
            }
        });
    };
    next();
 }; 
app.use(_blend);

route.js

app.get('/', function(req, res, next) {
    res.blend({
        buildData: function(params, callback) {
            GS.db.getRawData(params.id, callback);
        },
        buildSelectors: function(data, callback) {
            var selectors = GS.utils.generateGlobalSelectors(req);
            selectors['#widgets'] =  {
                partial: 'target',
                data: data
            };
            callback(selectors);
            GS.tracker.storeEvent('Targets:createTarget:load');
        },
        template: 'target',
        layout: GS.config.ui.layout,
        container: '#container'
    });
});