diff --git a/lib/controllers/uploader.js b/lib/controllers/uploader.js
index 2d2571f..96fcf77 100644
--- a/lib/controllers/uploader.js
+++ b/lib/controllers/uploader.js
@@ -27,6 +27,7 @@ var librarian = require('../common/api').librarian,
     EventEmitter = require('events').EventEmitter,
     util = require('util'),
     request = require('request');
+var _ = require('underscore');
 
 //-----------------------------------------------------------------------------
 /**
@@ -70,7 +71,7 @@ Uploader.prototype.upload = function (projectId, file, options) {
       method: 'PUT',
       uri: endpoint,
       timeout: 60 * 60 * 1000, // 1 hour
-      qs: Object.assign({ authToken: apiKey }, options),
+      qs: _.extend({ authToken: apiKey }, options),
       headers: { 'content-length': stat.size }
     };