diff --git a/lib/pipeline.js b/lib/pipeline.js
index 9dee03e..ae22bdd 100644
--- a/lib/pipeline.js
+++ b/lib/pipeline.js
@@ -1,4 +1,4 @@
-var Pipeline = module.exports = function (controller) {
+let Pipeline = module.exports = function (controller) {
   this.steps = [];
   this.controller = controller;
 }
@@ -8,8 +8,8 @@ Pipeline.prototype.addStep = function (step) {
 }
 
 Pipeline.prototype.run = function (frame) {
-  var stepsLength = this.steps.length;
-  for (var i = 0; i != stepsLength; i++) {
+  let stepsLength = this.steps.length;
+  for (let i = 0; i != stepsLength; i++) {
     if (!frame) break;
     frame = this.steps[i](frame);
   }
@@ -17,7 +17,7 @@ Pipeline.prototype.run = function (frame) {
 }
 
 Pipeline.prototype.removeStep = function(step){
-  var index = this.steps.indexOf(step);
+  let index = this.steps.indexOf(step);
   if (index === -1) throw "Step not found in pipeline";
   this.steps.splice(index, 1);
 }
@@ -36,9 +36,9 @@ Pipeline.prototype.removeStep = function(step){
  * @private
  */
 Pipeline.prototype.addWrappedStep = function (type, callback) {
-  var controller = this.controller,
+  let controller = this.controller,
     step = function (frame) {
-      var dependencies, i, len;
+      let dependencies, i, len;
       dependencies = (type == 'frame') ? [frame] : (frame[type + 's'] || []);
 
       for (i = 0, len = dependencies.length; i < len; i++) {
@@ -50,4 +50,4 @@ Pipeline.prototype.addWrappedStep = function (type, callback) {
 
   this.addStep(step);
   return step;
-};
\ No newline at end of file
+};