diff --git a/bower.json b/bower.json
index fa8370acee..4e46dc79b2 100644
--- a/bower.json
+++ b/bower.json
@@ -21,7 +21,6 @@
   "license": "MIT",
   "ignore": [
     "**/.*",
-    "*.iml",
     "examples",
     "lib",
     "node_modules",
diff --git a/lib/helpers/buildURL.js b/lib/helpers/buildURL.js
index 8c40e4096a..7a7d7a6199 100644
--- a/lib/helpers/buildURL.js
+++ b/lib/helpers/buildURL.js
@@ -39,7 +39,7 @@ module.exports = function buildURL(url, params, paramsSerializer) {
         return;
       }
 
-      if (utils.isArray(val)) {
+      if (Array.isArray(val)) {
         key = key + '[]';
       } else {
         val = [val];
diff --git a/lib/helpers/parseHeaders.js b/lib/helpers/parseHeaders.js
index 8af2cc7f1b..5747a1bd7a 100644
--- a/lib/helpers/parseHeaders.js
+++ b/lib/helpers/parseHeaders.js
@@ -34,8 +34,8 @@ module.exports = function parseHeaders(headers) {
 
   utils.forEach(headers.split('\n'), function parser(line) {
     i = line.indexOf(':');
-    key = utils.trim(line.substr(0, i)).toLowerCase();
-    val = utils.trim(line.substr(i + 1));
+    key = line.substr(0, i).trim().toLowerCase();
+    val = line.substr(i + 1).trim();
 
     if (key) {
       if (parsed[key] && ignoreDuplicateOf.indexOf(key) >= 0) {
diff --git a/lib/utils.js b/lib/utils.js
index e028c6763e..125f2be2a5 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -2,22 +2,10 @@
 
 var bind = require('./helpers/bind');
 
-/*global toString:true*/
-
 // utils is a library of generic helper functions non-specific to axios
 
 var toString = Object.prototype.toString;
 
-/**
- * Determine if a value is an Array
- *
- * @param {Object} val The value to test
- * @returns {boolean} True if value is an Array, otherwise false
- */
-function isArray(val) {
-  return toString.call(val) === '[object Array]';
-}
-
 /**
  * Determine if a value is undefined
  *
@@ -165,16 +153,6 @@ function isURLSearchParams(val) {
   return typeof URLSearchParams !== 'undefined' && val instanceof URLSearchParams;
 }
 
-/**
- * Trim excess whitespace off the beginning and end of a string
- *
- * @param {String} str The String to trim
- * @returns {String} The String freed of excess whitespace
- */
-function trim(str) {
-  return str.replace(/^\s*/, '').replace(/\s*$/, '');
-}
-
 /**
  * Determine if we're running in a standard browser environment
  *
@@ -226,7 +204,7 @@ function forEach(obj, fn) {
     obj = [obj];
   }
 
-  if (isArray(obj)) {
+  if (Array.isArray(obj)) {
     // Iterate over array values
     for (var i = 0, l = obj.length; i < l; i++) {
       fn.call(null, obj[i], i, obj);
@@ -320,7 +298,6 @@ function extend(a, b, thisArg) {
 }
 
 module.exports = {
-  isArray: isArray,
   isArrayBuffer: isArrayBuffer,
   isBuffer: isBuffer,
   isFormData: isFormData,
@@ -339,6 +316,5 @@ module.exports = {
   forEach: forEach,
   merge: merge,
   deepMerge: deepMerge,
-  extend: extend,
-  trim: trim
+  extend: extend
 };
diff --git a/package.json b/package.json
index cabd9e42b3..f1c73cc2a9 100644
--- a/package.json
+++ b/package.json
@@ -32,41 +32,39 @@
   },
   "homepage": "https://github.com/axios/axios",
   "devDependencies": {
-    "bundlesize": "^0.17.0",
-    "coveralls": "^3.0.0",
-    "es6-promise": "^4.2.4",
+    "bundlesize": "^0.18.0",
+    "coveralls": "^3.0.9",
     "grunt": "^1.0.2",
     "grunt-banner": "^0.6.0",
     "grunt-cli": "^1.2.0",
-    "grunt-contrib-clean": "^1.1.0",
+    "grunt-contrib-clean": "^2.0.0",
     "grunt-contrib-watch": "^1.0.0",
-    "grunt-eslint": "^20.1.0",
-    "grunt-karma": "^2.0.0",
+    "grunt-eslint": "^22.0.0",
+    "grunt-karma": "^3.0.2",
     "grunt-mocha-test": "^0.13.3",
     "grunt-ts": "^6.0.0-beta.19",
-    "grunt-webpack": "^1.0.18",
-    "istanbul-instrumenter-loader": "^1.0.0",
-    "jasmine-core": "^2.4.1",
-    "karma": "^1.3.0",
-    "karma-chrome-launcher": "^2.2.0",
-    "karma-coverage": "^1.1.1",
-    "karma-firefox-launcher": "^1.1.0",
-    "karma-jasmine": "^1.1.1",
+    "grunt-webpack": "^3.1.3",
+    "istanbul-instrumenter-loader": "^3.0.1",
+    "jasmine-core": "^3.5.0",
+    "karma": "^4.3.0",
+    "karma-chrome-launcher": "^3.1.0",
+    "karma-coverage": "^2.0.1",
+    "karma-firefox-launcher": "^1.3.0",
+    "karma-jasmine": "^3.1.0",
     "karma-jasmine-ajax": "^0.1.13",
     "karma-opera-launcher": "^1.0.0",
     "karma-safari-launcher": "^1.0.0",
-    "karma-sauce-launcher": "^1.2.0",
+    "karma-sauce-launcher": "^2.0.2",
     "karma-sinon": "^1.0.5",
     "karma-sourcemap-loader": "^0.3.7",
-    "karma-webpack": "^1.7.0",
-    "load-grunt-tasks": "^3.5.2",
+    "karma-webpack": "^4.0.2",
+    "load-grunt-tasks": "^5.1.0",
     "minimist": "^1.2.0",
-    "mocha": "^5.2.0",
-    "sinon": "^4.5.0",
+    "mocha": "^7.0.1",
+    "sinon": "^8.1.1",
     "typescript": "^2.8.1",
     "url-search-params": "^0.10.0",
-    "webpack": "^1.13.1",
-    "webpack-dev-server": "^1.14.1"
+    "webpack": "^4.40.2"
   },
   "browser": {
     "./lib/adapters/http.js": "./lib/adapters/xhr.js"
diff --git a/test/manual/basic.html b/test/manual/basic.html
index 35fa6490d8..978e0c5cf6 100644
--- a/test/manual/basic.html
+++ b/test/manual/basic.html
@@ -7,7 +7,10 @@
 
 An alert should be shown with the <code>{"name":"axios"}</code>
 
-<script src="promise.js"></script>
+<script>
+if (typeof Promise !== "function")
+    document.write('<script src="//cdnjs.cloudflare.com/ajax/libs/es6-promise/4.1.1/es6-promise.min.js"><\/script>');
+</script>
 <script src="../../dist/axios.js"></script>
 <script>
     axios.get('./fixture.json').then(function(response) {
@@ -18,4 +21,4 @@
 </script>
 
 </body>
-</html>
\ No newline at end of file
+</html>
diff --git a/test/manual/cors.html b/test/manual/cors.html
index da6e946fee..fb4519846e 100644
--- a/test/manual/cors.html
+++ b/test/manual/cors.html
@@ -7,7 +7,10 @@
 
 An alert should be shown with <code>{"status":"ok"}</code>
 
-<script src="promise.js"></script>
+<script>
+if (typeof Promise !== "function")
+    document.write('<script src="//cdnjs.cloudflare.com/ajax/libs/es6-promise/4.1.1/es6-promise.min.js"><\/script>');
+</script>
 <script src="../../dist/axios.js"></script>
 <script>
     axios.get('http://cors-test.appspot.com/test').then(function(response) {
@@ -17,4 +20,4 @@
 </script>
 
 </body>
-</html>
\ No newline at end of file
+</html>
diff --git a/test/manual/promise.js b/test/manual/promise.js
deleted file mode 100644
index 2d48351584..0000000000
--- a/test/manual/promise.js
+++ /dev/null
@@ -1,9 +0,0 @@
-/*!
- * @overview es6-promise - a tiny implementation of Promises/A+.
- * @copyright Copyright (c) 2014 Yehuda Katz, Tom Dale, Stefan Penner and contributors (Conversion to ES6 API by Jake Archibald)
- * @license   Licensed under MIT license
- *            See https://raw.githubusercontent.com/jakearchibald/es6-promise/master/LICENSE
- * @version   3.0.2
- */
-
-(function(){"use strict";function lib$es6$promise$utils$$objectOrFunction(x){return typeof x==="function"||typeof x==="object"&&x!==null}function lib$es6$promise$utils$$isFunction(x){return typeof x==="function"}function lib$es6$promise$utils$$isMaybeThenable(x){return typeof x==="object"&&x!==null}var lib$es6$promise$utils$$_isArray;if(!Array.isArray){lib$es6$promise$utils$$_isArray=function(x){return Object.prototype.toString.call(x)==="[object Array]"}}else{lib$es6$promise$utils$$_isArray=Array.isArray}var lib$es6$promise$utils$$isArray=lib$es6$promise$utils$$_isArray;var lib$es6$promise$asap$$len=0;var lib$es6$promise$asap$$toString={}.toString;var lib$es6$promise$asap$$vertxNext;var lib$es6$promise$asap$$customSchedulerFn;var lib$es6$promise$asap$$asap=function asap(callback,arg){lib$es6$promise$asap$$queue[lib$es6$promise$asap$$len]=callback;lib$es6$promise$asap$$queue[lib$es6$promise$asap$$len+1]=arg;lib$es6$promise$asap$$len+=2;if(lib$es6$promise$asap$$len===2){if(lib$es6$promise$asap$$customSchedulerFn){lib$es6$promise$asap$$customSchedulerFn(lib$es6$promise$asap$$flush)}else{lib$es6$promise$asap$$scheduleFlush()}}};function lib$es6$promise$asap$$setScheduler(scheduleFn){lib$es6$promise$asap$$customSchedulerFn=scheduleFn}function lib$es6$promise$asap$$setAsap(asapFn){lib$es6$promise$asap$$asap=asapFn}var lib$es6$promise$asap$$browserWindow=typeof window!=="undefined"?window:undefined;var lib$es6$promise$asap$$browserGlobal=lib$es6$promise$asap$$browserWindow||{};var lib$es6$promise$asap$$BrowserMutationObserver=lib$es6$promise$asap$$browserGlobal.MutationObserver||lib$es6$promise$asap$$browserGlobal.WebKitMutationObserver;var lib$es6$promise$asap$$isNode=typeof process!=="undefined"&&{}.toString.call(process)==="[object process]";var lib$es6$promise$asap$$isWorker=typeof Uint8ClampedArray!=="undefined"&&typeof importScripts!=="undefined"&&typeof MessageChannel!=="undefined";function lib$es6$promise$asap$$useNextTick(){return function(){process.nextTick(lib$es6$promise$asap$$flush)}}function lib$es6$promise$asap$$useVertxTimer(){return function(){lib$es6$promise$asap$$vertxNext(lib$es6$promise$asap$$flush)}}function lib$es6$promise$asap$$useMutationObserver(){var iterations=0;var observer=new lib$es6$promise$asap$$BrowserMutationObserver(lib$es6$promise$asap$$flush);var node=document.createTextNode("");observer.observe(node,{characterData:true});return function(){node.data=iterations=++iterations%2}}function lib$es6$promise$asap$$useMessageChannel(){var channel=new MessageChannel;channel.port1.onmessage=lib$es6$promise$asap$$flush;return function(){channel.port2.postMessage(0)}}function lib$es6$promise$asap$$useSetTimeout(){return function(){setTimeout(lib$es6$promise$asap$$flush,1)}}var lib$es6$promise$asap$$queue=new Array(1e3);function lib$es6$promise$asap$$flush(){for(var i=0;i<lib$es6$promise$asap$$len;i+=2){var callback=lib$es6$promise$asap$$queue[i];var arg=lib$es6$promise$asap$$queue[i+1];callback(arg);lib$es6$promise$asap$$queue[i]=undefined;lib$es6$promise$asap$$queue[i+1]=undefined}lib$es6$promise$asap$$len=0}function lib$es6$promise$asap$$attemptVertx(){try{var r=require;var vertx=r("vertx");lib$es6$promise$asap$$vertxNext=vertx.runOnLoop||vertx.runOnContext;return lib$es6$promise$asap$$useVertxTimer()}catch(e){return lib$es6$promise$asap$$useSetTimeout()}}var lib$es6$promise$asap$$scheduleFlush;if(lib$es6$promise$asap$$isNode){lib$es6$promise$asap$$scheduleFlush=lib$es6$promise$asap$$useNextTick()}else if(lib$es6$promise$asap$$BrowserMutationObserver){lib$es6$promise$asap$$scheduleFlush=lib$es6$promise$asap$$useMutationObserver()}else if(lib$es6$promise$asap$$isWorker){lib$es6$promise$asap$$scheduleFlush=lib$es6$promise$asap$$useMessageChannel()}else if(lib$es6$promise$asap$$browserWindow===undefined&&typeof require==="function"){lib$es6$promise$asap$$scheduleFlush=lib$es6$promise$asap$$attemptVertx()}else{lib$es6$promise$asap$$scheduleFlush=lib$es6$promise$asap$$useSetTimeout()}function lib$es6$promise$$internal$$noop(){}var lib$es6$promise$$internal$$PENDING=void 0;var lib$es6$promise$$internal$$FULFILLED=1;var lib$es6$promise$$internal$$REJECTED=2;var lib$es6$promise$$internal$$GET_THEN_ERROR=new lib$es6$promise$$internal$$ErrorObject;function lib$es6$promise$$internal$$selfFulfillment(){return new TypeError("You cannot resolve a promise with itself")}function lib$es6$promise$$internal$$cannotReturnOwn(){return new TypeError("A promises callback cannot return that same promise.")}function lib$es6$promise$$internal$$getThen(promise){try{return promise.then}catch(error){lib$es6$promise$$internal$$GET_THEN_ERROR.error=error;return lib$es6$promise$$internal$$GET_THEN_ERROR}}function lib$es6$promise$$internal$$tryThen(then,value,fulfillmentHandler,rejectionHandler){try{then.call(value,fulfillmentHandler,rejectionHandler)}catch(e){return e}}function lib$es6$promise$$internal$$handleForeignThenable(promise,thenable,then){lib$es6$promise$asap$$asap(function(promise){var sealed=false;var error=lib$es6$promise$$internal$$tryThen(then,thenable,function(value){if(sealed){return}sealed=true;if(thenable!==value){lib$es6$promise$$internal$$resolve(promise,value)}else{lib$es6$promise$$internal$$fulfill(promise,value)}},function(reason){if(sealed){return}sealed=true;lib$es6$promise$$internal$$reject(promise,reason)},"Settle: "+(promise._label||" unknown promise"));if(!sealed&&error){sealed=true;lib$es6$promise$$internal$$reject(promise,error)}},promise)}function lib$es6$promise$$internal$$handleOwnThenable(promise,thenable){if(thenable._state===lib$es6$promise$$internal$$FULFILLED){lib$es6$promise$$internal$$fulfill(promise,thenable._result)}else if(thenable._state===lib$es6$promise$$internal$$REJECTED){lib$es6$promise$$internal$$reject(promise,thenable._result)}else{lib$es6$promise$$internal$$subscribe(thenable,undefined,function(value){lib$es6$promise$$internal$$resolve(promise,value)},function(reason){lib$es6$promise$$internal$$reject(promise,reason)})}}function lib$es6$promise$$internal$$handleMaybeThenable(promise,maybeThenable){if(maybeThenable.constructor===promise.constructor){lib$es6$promise$$internal$$handleOwnThenable(promise,maybeThenable)}else{var then=lib$es6$promise$$internal$$getThen(maybeThenable);if(then===lib$es6$promise$$internal$$GET_THEN_ERROR){lib$es6$promise$$internal$$reject(promise,lib$es6$promise$$internal$$GET_THEN_ERROR.error)}else if(then===undefined){lib$es6$promise$$internal$$fulfill(promise,maybeThenable)}else if(lib$es6$promise$utils$$isFunction(then)){lib$es6$promise$$internal$$handleForeignThenable(promise,maybeThenable,then)}else{lib$es6$promise$$internal$$fulfill(promise,maybeThenable)}}}function lib$es6$promise$$internal$$resolve(promise,value){if(promise===value){lib$es6$promise$$internal$$reject(promise,lib$es6$promise$$internal$$selfFulfillment())}else if(lib$es6$promise$utils$$objectOrFunction(value)){lib$es6$promise$$internal$$handleMaybeThenable(promise,value)}else{lib$es6$promise$$internal$$fulfill(promise,value)}}function lib$es6$promise$$internal$$publishRejection(promise){if(promise._onerror){promise._onerror(promise._result)}lib$es6$promise$$internal$$publish(promise)}function lib$es6$promise$$internal$$fulfill(promise,value){if(promise._state!==lib$es6$promise$$internal$$PENDING){return}promise._result=value;promise._state=lib$es6$promise$$internal$$FULFILLED;if(promise._subscribers.length!==0){lib$es6$promise$asap$$asap(lib$es6$promise$$internal$$publish,promise)}}function lib$es6$promise$$internal$$reject(promise,reason){if(promise._state!==lib$es6$promise$$internal$$PENDING){return}promise._state=lib$es6$promise$$internal$$REJECTED;promise._result=reason;lib$es6$promise$asap$$asap(lib$es6$promise$$internal$$publishRejection,promise)}function lib$es6$promise$$internal$$subscribe(parent,child,onFulfillment,onRejection){var subscribers=parent._subscribers;var length=subscribers.length;parent._onerror=null;subscribers[length]=child;subscribers[length+lib$es6$promise$$internal$$FULFILLED]=onFulfillment;subscribers[length+lib$es6$promise$$internal$$REJECTED]=onRejection;if(length===0&&parent._state){lib$es6$promise$asap$$asap(lib$es6$promise$$internal$$publish,parent)}}function lib$es6$promise$$internal$$publish(promise){var subscribers=promise._subscribers;var settled=promise._state;if(subscribers.length===0){return}var child,callback,detail=promise._result;for(var i=0;i<subscribers.length;i+=3){child=subscribers[i];callback=subscribers[i+settled];if(child){lib$es6$promise$$internal$$invokeCallback(settled,child,callback,detail)}else{callback(detail)}}promise._subscribers.length=0}function lib$es6$promise$$internal$$ErrorObject(){this.error=null}var lib$es6$promise$$internal$$TRY_CATCH_ERROR=new lib$es6$promise$$internal$$ErrorObject;function lib$es6$promise$$internal$$tryCatch(callback,detail){try{return callback(detail)}catch(e){lib$es6$promise$$internal$$TRY_CATCH_ERROR.error=e;return lib$es6$promise$$internal$$TRY_CATCH_ERROR}}function lib$es6$promise$$internal$$invokeCallback(settled,promise,callback,detail){var hasCallback=lib$es6$promise$utils$$isFunction(callback),value,error,succeeded,failed;if(hasCallback){value=lib$es6$promise$$internal$$tryCatch(callback,detail);if(value===lib$es6$promise$$internal$$TRY_CATCH_ERROR){failed=true;error=value.error;value=null}else{succeeded=true}if(promise===value){lib$es6$promise$$internal$$reject(promise,lib$es6$promise$$internal$$cannotReturnOwn());return}}else{value=detail;succeeded=true}if(promise._state!==lib$es6$promise$$internal$$PENDING){}else if(hasCallback&&succeeded){lib$es6$promise$$internal$$resolve(promise,value)}else if(failed){lib$es6$promise$$internal$$reject(promise,error)}else if(settled===lib$es6$promise$$internal$$FULFILLED){lib$es6$promise$$internal$$fulfill(promise,value)}else if(settled===lib$es6$promise$$internal$$REJECTED){lib$es6$promise$$internal$$reject(promise,value)}}function lib$es6$promise$$internal$$initializePromise(promise,resolver){try{resolver(function resolvePromise(value){lib$es6$promise$$internal$$resolve(promise,value)},function rejectPromise(reason){lib$es6$promise$$internal$$reject(promise,reason)})}catch(e){lib$es6$promise$$internal$$reject(promise,e)}}function lib$es6$promise$enumerator$$Enumerator(Constructor,input){var enumerator=this;enumerator._instanceConstructor=Constructor;enumerator.promise=new Constructor(lib$es6$promise$$internal$$noop);if(enumerator._validateInput(input)){enumerator._input=input;enumerator.length=input.length;enumerator._remaining=input.length;enumerator._init();if(enumerator.length===0){lib$es6$promise$$internal$$fulfill(enumerator.promise,enumerator._result)}else{enumerator.length=enumerator.length||0;enumerator._enumerate();if(enumerator._remaining===0){lib$es6$promise$$internal$$fulfill(enumerator.promise,enumerator._result)}}}else{lib$es6$promise$$internal$$reject(enumerator.promise,enumerator._validationError())}}lib$es6$promise$enumerator$$Enumerator.prototype._validateInput=function(input){return lib$es6$promise$utils$$isArray(input)};lib$es6$promise$enumerator$$Enumerator.prototype._validationError=function(){return new Error("Array Methods must be provided an Array")};lib$es6$promise$enumerator$$Enumerator.prototype._init=function(){this._result=new Array(this.length)};var lib$es6$promise$enumerator$$default=lib$es6$promise$enumerator$$Enumerator;lib$es6$promise$enumerator$$Enumerator.prototype._enumerate=function(){var enumerator=this;var length=enumerator.length;var promise=enumerator.promise;var input=enumerator._input;for(var i=0;promise._state===lib$es6$promise$$internal$$PENDING&&i<length;i++){enumerator._eachEntry(input[i],i)}};lib$es6$promise$enumerator$$Enumerator.prototype._eachEntry=function(entry,i){var enumerator=this;var c=enumerator._instanceConstructor;if(lib$es6$promise$utils$$isMaybeThenable(entry)){if(entry.constructor===c&&entry._state!==lib$es6$promise$$internal$$PENDING){entry._onerror=null;enumerator._settledAt(entry._state,i,entry._result)}else{enumerator._willSettleAt(c.resolve(entry),i)}}else{enumerator._remaining--;enumerator._result[i]=entry}};lib$es6$promise$enumerator$$Enumerator.prototype._settledAt=function(state,i,value){var enumerator=this;var promise=enumerator.promise;if(promise._state===lib$es6$promise$$internal$$PENDING){enumerator._remaining--;if(state===lib$es6$promise$$internal$$REJECTED){lib$es6$promise$$internal$$reject(promise,value)}else{enumerator._result[i]=value}}if(enumerator._remaining===0){lib$es6$promise$$internal$$fulfill(promise,enumerator._result)}};lib$es6$promise$enumerator$$Enumerator.prototype._willSettleAt=function(promise,i){var enumerator=this;lib$es6$promise$$internal$$subscribe(promise,undefined,function(value){enumerator._settledAt(lib$es6$promise$$internal$$FULFILLED,i,value)},function(reason){enumerator._settledAt(lib$es6$promise$$internal$$REJECTED,i,reason)})};function lib$es6$promise$promise$all$$all(entries){return new lib$es6$promise$enumerator$$default(this,entries).promise}var lib$es6$promise$promise$all$$default=lib$es6$promise$promise$all$$all;function lib$es6$promise$promise$race$$race(entries){var Constructor=this;var promise=new Constructor(lib$es6$promise$$internal$$noop);if(!lib$es6$promise$utils$$isArray(entries)){lib$es6$promise$$internal$$reject(promise,new TypeError("You must pass an array to race."));return promise}var length=entries.length;function onFulfillment(value){lib$es6$promise$$internal$$resolve(promise,value)}function onRejection(reason){lib$es6$promise$$internal$$reject(promise,reason)}for(var i=0;promise._state===lib$es6$promise$$internal$$PENDING&&i<length;i++){lib$es6$promise$$internal$$subscribe(Constructor.resolve(entries[i]),undefined,onFulfillment,onRejection)}return promise}var lib$es6$promise$promise$race$$default=lib$es6$promise$promise$race$$race;function lib$es6$promise$promise$resolve$$resolve(object){var Constructor=this;if(object&&typeof object==="object"&&object.constructor===Constructor){return object}var promise=new Constructor(lib$es6$promise$$internal$$noop);lib$es6$promise$$internal$$resolve(promise,object);return promise}var lib$es6$promise$promise$resolve$$default=lib$es6$promise$promise$resolve$$resolve;function lib$es6$promise$promise$reject$$reject(reason){var Constructor=this;var promise=new Constructor(lib$es6$promise$$internal$$noop);lib$es6$promise$$internal$$reject(promise,reason);return promise}var lib$es6$promise$promise$reject$$default=lib$es6$promise$promise$reject$$reject;var lib$es6$promise$promise$$counter=0;function lib$es6$promise$promise$$needsResolver(){throw new TypeError("You must pass a resolver function as the first argument to the promise constructor")}function lib$es6$promise$promise$$needsNew(){throw new TypeError("Failed to construct 'Promise': Please use the 'new' operator, this object constructor cannot be called as a function.")}var lib$es6$promise$promise$$default=lib$es6$promise$promise$$Promise;function lib$es6$promise$promise$$Promise(resolver){this._id=lib$es6$promise$promise$$counter++;this._state=undefined;this._result=undefined;this._subscribers=[];if(lib$es6$promise$$internal$$noop!==resolver){if(!lib$es6$promise$utils$$isFunction(resolver)){lib$es6$promise$promise$$needsResolver()}if(!(this instanceof lib$es6$promise$promise$$Promise)){lib$es6$promise$promise$$needsNew()}lib$es6$promise$$internal$$initializePromise(this,resolver)}}lib$es6$promise$promise$$Promise.all=lib$es6$promise$promise$all$$default;lib$es6$promise$promise$$Promise.race=lib$es6$promise$promise$race$$default;lib$es6$promise$promise$$Promise.resolve=lib$es6$promise$promise$resolve$$default;lib$es6$promise$promise$$Promise.reject=lib$es6$promise$promise$reject$$default;lib$es6$promise$promise$$Promise._setScheduler=lib$es6$promise$asap$$setScheduler;lib$es6$promise$promise$$Promise._setAsap=lib$es6$promise$asap$$setAsap;lib$es6$promise$promise$$Promise._asap=lib$es6$promise$asap$$asap;lib$es6$promise$promise$$Promise.prototype={constructor:lib$es6$promise$promise$$Promise,then:function(onFulfillment,onRejection){var parent=this;var state=parent._state;if(state===lib$es6$promise$$internal$$FULFILLED&&!onFulfillment||state===lib$es6$promise$$internal$$REJECTED&&!onRejection){return this}var child=new this.constructor(lib$es6$promise$$internal$$noop);var result=parent._result;if(state){var callback=arguments[state-1];lib$es6$promise$asap$$asap(function(){lib$es6$promise$$internal$$invokeCallback(state,child,callback,result)})}else{lib$es6$promise$$internal$$subscribe(parent,child,onFulfillment,onRejection)}return child},"catch":function(onRejection){return this.then(null,onRejection)}};function lib$es6$promise$polyfill$$polyfill(){var local;if(typeof global!=="undefined"){local=global}else if(typeof self!=="undefined"){local=self}else{try{local=Function("return this")()}catch(e){throw new Error("polyfill failed because global object is unavailable in this environment")}}var P=local.Promise;if(P&&Object.prototype.toString.call(P.resolve())==="[object Promise]"&&!P.cast){return}local.Promise=lib$es6$promise$promise$$default}var lib$es6$promise$polyfill$$default=lib$es6$promise$polyfill$$polyfill;var lib$es6$promise$umd$$ES6Promise={Promise:lib$es6$promise$promise$$default,polyfill:lib$es6$promise$polyfill$$default};if(typeof define==="function"&&define["amd"]){define(function(){return lib$es6$promise$umd$$ES6Promise})}else if(typeof module!=="undefined"&&module["exports"]){module["exports"]=lib$es6$promise$umd$$ES6Promise}else if(typeof this!=="undefined"){this["ES6Promise"]=lib$es6$promise$umd$$ES6Promise}lib$es6$promise$polyfill$$default()}).call(this);
\ No newline at end of file
diff --git a/test/specs/__helpers.js b/test/specs/__helpers.js
index efb4fc6410..68d27f3a9b 100644
--- a/test/specs/__helpers.js
+++ b/test/specs/__helpers.js
@@ -1,6 +1,3 @@
-// Polyfill ES6 Promise
-require('es6-promise').polyfill();
-
 // Polyfill URLSearchParams
 URLSearchParams = require('url-search-params');
 
diff --git a/test/specs/utils/isX.spec.js b/test/specs/utils/isX.spec.js
index 2d301c730d..fec84b93f4 100644
--- a/test/specs/utils/isX.spec.js
+++ b/test/specs/utils/isX.spec.js
@@ -2,11 +2,6 @@ var utils = require('../../../lib/utils');
 var Stream = require('stream');
 
 describe('utils::isX', function () {
-  it('should validate Array', function () {
-    expect(utils.isArray([])).toEqual(true);
-    expect(utils.isArray({length: 5})).toEqual(false);
-  });
-
   it('should validate Buffer', function () {
     expect(utils.isBuffer(Buffer.from('a'))).toEqual(true);
     expect(utils.isBuffer(null)).toEqual(false);
diff --git a/test/specs/utils/trim.spec.js b/test/specs/utils/trim.spec.js
deleted file mode 100644
index 1b45e953ef..0000000000
--- a/test/specs/utils/trim.spec.js
+++ /dev/null
@@ -1,12 +0,0 @@
-var trim = require('../../../lib/utils').trim;
-
-describe('utils::trim', function () {
-  it('should trim spaces', function () {
-    expect(trim('  foo  ')).toEqual('foo');
-  });
-
-  it('should trim tabs', function () {
-    expect(trim('\tfoo\t')).toEqual('foo');
-  });
-});
-
diff --git a/webpack.config.js b/webpack.config.js
index 1a3e5b5317..3917a38221 100644
--- a/webpack.config.js
+++ b/webpack.config.js
@@ -1,12 +1,13 @@
-var webpack = require('webpack');
-var config = {};
+const webpack = require('webpack');
+const TerserPlugin = require('terser-webpack-plugin');
+const config = {};
 
 function generateConfig(name) {
-  var uglify = name.indexOf('min') > -1;
-  var config = {
+  return {
+    mode: 'production',
     entry: './index.js',
     output: {
-      path: 'dist/',
+      path: `${__dirname}/dist`,
       filename: name + '.js',
       sourceMapFilename: name + '.map',
       library: 'axios',
@@ -15,30 +16,21 @@ function generateConfig(name) {
     node: {
       process: false
     },
-    devtool: 'source-map'
+    devtool: 'source-map',
+    optimization: {
+      minimize: name.includes('min'),
+      minimizer: [
+        // config options documented at https://github.com/webpack-contrib/terser-webpack-plugin#terseroptions
+        new TerserPlugin({
+          sourceMap: true,
+        }),
+      ],
+    },
   };
-
-  config.plugins = [
-    new webpack.DefinePlugin({
-      'process.env.NODE_ENV': JSON.stringify(process.env.NODE_ENV)
-    })
-  ];
-
-  if (uglify) {
-    config.plugins.push(
-      new webpack.optimize.UglifyJsPlugin({
-        compressor: {
-          warnings: false
-        }
-      })
-    );
-  }
-
-  return config;
 }
 
-['axios', 'axios.min'].forEach(function (key) {
-  config[key] = generateConfig(key);
+['axios', 'axios.min'].forEach(outputScript => {
+  config[outputScript] = generateConfig(outputScript);
 });
 
 module.exports = config;