diff --git a/dist/amd/index.js b/dist/amd/index.js
index 4d075de..dc7d021 100644
--- a/dist/amd/index.js
+++ b/dist/amd/index.js
@@ -6,8 +6,10 @@ define(['exports', 'aurelia-templating', './animator'], function (exports, _aure
   exports.CssAnimator = _animator.CssAnimator;
 
   function configure(aurelia, cb) {
-    var animator = new _animator.CssAnimator();
+    var animator = aurelia.container.get(_animator.CssAnimator);
     _aureliaTemplating.Animator.configureDefault(aurelia.container, animator);
-    cb(aurelia.container.get(_animator.CssAnimator));
+    if (cb !== undefined && typeof cb === 'function') {
+      cb(animator);
+    }
   }
 });
\ No newline at end of file
diff --git a/dist/commonjs/index.js b/dist/commonjs/index.js
index 1da2296..c8d7168 100644
--- a/dist/commonjs/index.js
+++ b/dist/commonjs/index.js
@@ -10,7 +10,9 @@ var _CssAnimator = require('./animator');
 exports.CssAnimator = _CssAnimator.CssAnimator;
 
 function configure(aurelia, cb) {
-  var animator = new _CssAnimator.CssAnimator();
+  var animator = aurelia.container.get(_CssAnimator.CssAnimator);
   _Animator.Animator.configureDefault(aurelia.container, animator);
-  cb(aurelia.container.get(_CssAnimator.CssAnimator));
+  if (cb !== undefined && typeof cb === 'function') {
+    cb(animator);
+  }
 }
\ No newline at end of file
diff --git a/dist/es6/index.js b/dist/es6/index.js
index 709dc8d..695049a 100644
--- a/dist/es6/index.js
+++ b/dist/es6/index.js
@@ -4,7 +4,9 @@ import {CssAnimator} from './animator';
 export {CssAnimator} from './animator';
 
 export function configure(aurelia, cb){
-  var animator = new CssAnimator();
+  var animator = aurelia.container.get(CssAnimator);
   Animator.configureDefault(aurelia.container, animator);
-  cb(aurelia.container.get(CssAnimator));
+  if(cb !== undefined && typeof(cb) === 'function') {
+    cb(animator);
+  }
 }
diff --git a/dist/system/index.js b/dist/system/index.js
index 3046fa7..be99e9e 100644
--- a/dist/system/index.js
+++ b/dist/system/index.js
@@ -4,9 +4,11 @@ System.register(['aurelia-templating', './animator'], function (_export) {
   _export('configure', configure);
 
   function configure(aurelia, cb) {
-    var animator = new CssAnimator();
+    var animator = aurelia.container.get(CssAnimator);
     Animator.configureDefault(aurelia.container, animator);
-    cb(aurelia.container.get(CssAnimator));
+    if (cb !== undefined && typeof cb === 'function') {
+      cb(animator);
+    }
   }
 
   return {
diff --git a/src/index.js b/src/index.js
index 709dc8d..695049a 100644
--- a/src/index.js
+++ b/src/index.js
@@ -4,7 +4,9 @@ import {CssAnimator} from './animator';
 export {CssAnimator} from './animator';
 
 export function configure(aurelia, cb){
-  var animator = new CssAnimator();
+  var animator = aurelia.container.get(CssAnimator);
   Animator.configureDefault(aurelia.container, animator);
-  cb(aurelia.container.get(CssAnimator));
+  if(cb !== undefined && typeof(cb) === 'function') {
+    cb(animator);
+  }
 }