code: function (req, res, next) {
      var file = target(fss.source(req.path)) || '';
      var type = fss.filetype(file) || 'html';
      var mime = filter.get('mime', fss.filetype(file))();
  
      if (!fss.exists(file)) {
          res.status(404);
          res.send('404');
          return;
      }
  
      if (filter.has('compile', type)) {
          pacbot.compile(file, {}, function(content) {
              res.type(mime);
              res.send(content);
          });
      } else {
          next();
      }
  }
docs: /*
  Process requests on the fly, or forward it to the static file handler.