diff --git a/lib/index.js b/lib/index.js
index 9b8f8f1..9c0d38f 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -5,6 +5,7 @@ var root = (os.platform === 'win32') ? process.cwd().split(path.sep)[0] : '/'
 var log = require('npmlog')
 var gitUrlParse = require('git-url-parse')
 var inquire = require('./util/inquire')
+var assign = require('object.assign/polyfill')()
 
 function checkGitVersion (path, nr) {
   return createGitExec(path)('version').then(function (data) {
@@ -109,7 +110,7 @@ function runMethod (title, mode, input, remote) {
       require('./util/art')
         .logoWithText(title, process.stdout.columns)
     )
-    var allCommands = Object.assign(Object.assign({}, mode), {
+    var allCommands = assign(assign({}, mode), {
       help: help,
       exit: exit
     })
diff --git a/package.json b/package.json
index 87347f1..d3afcec 100644
--- a/package.json
+++ b/package.json
@@ -60,9 +60,10 @@
     "nodegit": "^0.8.0",
     "nopt": "^3.0.6",
     "npmlog": "^2.0.0",
+    "object.assign": "^4.0.3",
+    "progress": "^1.1.8",
     "semver-compare": "^1.0.0",
-    "tz-lookup": "^6.0.2",
-    "progress": "^1.1.8"
+    "tz-lookup": "^6.0.2"
   },
   "repository": {
     "type": "git",