diff --git a/demo/knockout.html b/demo/knockout.html
index 84301da..7ddf073 100644
--- a/demo/knockout.html
+++ b/demo/knockout.html
@@ -17,7 +17,7 @@
     <script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
     <script src="//cdnjs.cloudflare.com/ajax/libs/jqueryui/1.11.0/jquery-ui.js"></script>
     <script src="//maxcdn.bootstrapcdn.com/bootstrap/3.2.0/js/bootstrap.min.js"></script>
-    <script src="//cdnjs.cloudflare.com/ajax/libs/underscore.js/1.7.0/underscore-min.js"></script>
+    <script src="//cdnjs.cloudflare.com/ajax/libs/lodash.js/3.5.0/lodash.min.js"></script>
     <script src="//cdnjs.cloudflare.com/ajax/libs/knockout/3.2.0/knockout-min.js"></script>
     <script src="../gridstack.js"></script>
 
diff --git a/demo/knockout2.html b/demo/knockout2.html
index e753510..d7c5331 100644
--- a/demo/knockout2.html
+++ b/demo/knockout2.html
@@ -17,7 +17,7 @@
     <script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
     <script src="//cdnjs.cloudflare.com/ajax/libs/jqueryui/1.11.0/jquery-ui.js"></script>
     <script src="//maxcdn.bootstrapcdn.com/bootstrap/3.2.0/js/bootstrap.min.js"></script>
-    <script src="//cdnjs.cloudflare.com/ajax/libs/underscore.js/1.7.0/underscore-min.js"></script>
+    <script src="//cdnjs.cloudflare.com/ajax/libs/lodash.js/3.5.0/lodash.min.js"></script>
     <script src="//cdnjs.cloudflare.com/ajax/libs/knockout/3.2.0/knockout-min.js"></script>
     <script src="../gridstack.js"></script>
 
diff --git a/demo/nested.html b/demo/nested.html
index 920e72e..270285e 100644
--- a/demo/nested.html
+++ b/demo/nested.html
@@ -17,7 +17,7 @@
     <script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
     <script src="//cdnjs.cloudflare.com/ajax/libs/jqueryui/1.11.0/jquery-ui.js"></script>
     <script src="//maxcdn.bootstrapcdn.com/bootstrap/3.2.0/js/bootstrap.min.js"></script>
-    <script src="//cdnjs.cloudflare.com/ajax/libs/underscore.js/1.7.0/underscore-min.js"></script>
+    <script src="//cdnjs.cloudflare.com/ajax/libs/lodash.js/3.5.0/lodash.min.js"></script>
     <script src="../gridstack.js"></script>
 
     <style type="text/css">
diff --git a/demo/serialization.html b/demo/serialization.html
index 5e4a8ec..8190daa 100644
--- a/demo/serialization.html
+++ b/demo/serialization.html
@@ -17,7 +17,7 @@
     <script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
     <script src="//cdnjs.cloudflare.com/ajax/libs/jqueryui/1.11.0/jquery-ui.js"></script>
     <script src="//maxcdn.bootstrapcdn.com/bootstrap/3.2.0/js/bootstrap.min.js"></script>
-    <script src="//cdnjs.cloudflare.com/ajax/libs/underscore.js/1.7.0/underscore-min.js"></script>
+    <script src="//cdnjs.cloudflare.com/ajax/libs/lodash.js/3.5.0/lodash.min.js"></script>
     <script src="../gridstack.js"></script>
 
     <style type="text/css">
diff --git a/gridstack.js b/gridstack.js
index 59b0c78..06b45fd 100644
--- a/gridstack.js
+++ b/gridstack.js
@@ -5,7 +5,7 @@
 
 (function (factory) {
     if (typeof define === 'function' && define.amd) {
-        define(['jquery', 'underscore'], factory);
+        define(['jquery', 'lodash'], factory);
     }
     else {
         factory(jQuery, _);
@@ -153,7 +153,7 @@
 
                     if (i > 0) {
                         var collision_node = _.chain(this.nodes)
-                            .first(i)
+                            .take(i)
                             .find(function (bn) {
                                 return Utils.is_intercepted({x: n.x, y: new_y, width: n.width, height: n.height}, bn);
                             })
@@ -435,7 +435,7 @@
             });
             _.chain(elements).sortBy(function (x) { return x.i; }).each(function (i) {
                 self._prepare_element(i.el);
-            });
+            }).value();
         }
 
         this.set_animation(this.opts.animate);
diff --git a/index.html b/index.html
index 16e67a1..9187286 100644
--- a/index.html
+++ b/index.html
@@ -188,7 +188,7 @@ $(function () {
     <script src="jquery-ui.min.js"></script>
     <script src="jquery.ui.touch-punch.min.js"></script>
     <script src="//maxcdn.bootstrapcdn.com/bootstrap/3.2.0/js/bootstrap.min.js"></script>
-    <script src="//cdnjs.cloudflare.com/ajax/libs/underscore.js/1.7.0/underscore-min.js"></script>
+    <script src="//cdnjs.cloudflare.com/ajax/libs/lodash.js/3.5.0/lodash.min.js"></script>
 
     <!-- Plugin JavaScript -->
     <script src="//cdnjs.cloudflare.com/ajax/libs/jquery-easing/1.3/jquery.easing.min.js"></script>