code: function (next) {
  
          async.map(files, function (path, done) {
              fs.readFile(path, {
                  encoding: 'utf8'
              }, function (err, data) {
                  done(err, {
                      path: path,
                      code: data
                  });
              });
          }, function (err, codes) {
              if (err) return next(err);
              try {
                  next(null, fume(codes));
              } catch (err) {
                  next(err);
              }
          });
  
      }
docs: fume files