diff --git a/.jshintrc b/.jshintrc
index cf86db2c..d730076b 100644
--- a/.jshintrc
+++ b/.jshintrc
@@ -59,7 +59,7 @@
     "evil"          : false,    // Tolerate use of `eval`.
     "expr"          : true,     // Tolerate `ExpressionStatement` as Programs.
     "funcscope"     : false,    // Tolerate declarations of variables inside of control structures while accessing them later from the outside.
-    "globalstrict"  : false,    // Allow global "use strict" (also enables 'strict').
+    "globalstrict"  : true,     // Allow global "use strict" (also enables 'strict').
     "iterator"      : false,    // Allow usage of __iterator__ property.
     "lastsemic"     : false,    // Tolerat missing semicolons when the it is omitted for the last statement in a one-line block.
     "laxbreak"      : false,    // Tolerate unsafe line breaks e.g. `return [\n] x` without semicolons.
diff --git a/gulpfile.js b/gulpfile.js
index 9ed51bbd..871c033c 100644
--- a/gulpfile.js
+++ b/gulpfile.js
@@ -14,13 +14,15 @@
  * limitations under the License.
  */
 
-var gulp = require('gulp');
-var jscs = require('gulp-jscs');
-var jshint = require('gulp-jshint');
-var jshintStylish = require('jshint-stylish');
-var sass = require('gulp-sass');
+'use strict';
 
-var paths = {
+const gulp = require('gulp');
+const jscs = require('gulp-jscs');
+const jshint = require('gulp-jshint');
+const jshintStylish = require('jshint-stylish');
+const sass = require('gulp-sass');
+
+const paths = {
   scripts: [
     './tests/**/*.spec.js',
     './lib/**/*.js',
@@ -32,16 +34,12 @@ var paths = {
 };
 
 gulp.task('sass', function() {
-  'use strict';
-
   return gulp.src(paths.sass)
     .pipe(sass().on('error', sass.logError))
     .pipe(gulp.dest('./build/css'));
 });
 
 gulp.task('lint', function() {
-  'use strict';
-
   return gulp.src(paths.scripts)
     .pipe(jshint())
     .pipe(jshint.reporter(jshintStylish))
@@ -50,8 +48,6 @@ gulp.task('lint', function() {
 });
 
 gulp.task('watch', [ 'lint', 'sass' ], function() {
-  'use strict';
-
   gulp.watch(paths.scripts, [ 'lint' ]);
   gulp.watch(paths.sass, [ 'sass' ]);
 });
diff --git a/lib/browser/app.js b/lib/browser/app.js
index be9e4c51..bd66d95f 100644
--- a/lib/browser/app.js
+++ b/lib/browser/app.js
@@ -18,11 +18,13 @@
  * @module ResinEtcher
  */
 
+'use strict';
+
 var angular = require('angular');
-var _ = require('lodash');
-var electron = require('electron');
-var shell = electron.remote.require('shell');
-var dialog = electron.remote.require('./src/dialog');
+const _ = require('lodash');
+const electron = require('electron');
+const shell = electron.remote.require('shell');
+const dialog = electron.remote.require('./src/dialog');
 
 require('angular-ui-bootstrap');
 require('./browser/modules/selection-state');
@@ -30,7 +32,7 @@ require('./browser/modules/drive-scanner');
 require('./browser/modules/image-writer');
 require('./browser/modules/path');
 
-var app = angular.module('ResinEtcher', [
+const app = angular.module('ResinEtcher', [
   'ui.bootstrap',
 
   // Resin Etcher modules
@@ -43,8 +45,6 @@ var app = angular.module('ResinEtcher', [
 // TrackJS integration
 // http://docs.trackjs.com/tracker/framework-integrations
 app.config(function($provide) {
-  'use strict';
-
   $provide.decorator('$exceptionHandler', function($delegate, $window) {
     return function(exception, cause) {
       $window.trackJs.track(exception);
@@ -55,7 +55,7 @@ app.config(function($provide) {
   $provide.decorator('$log', function($delegate, $window) {
 
     // Save the original $log.debug()
-    var debugFn = $delegate.debug;
+    let debugFn = $delegate.debug;
 
     $delegate.debug = function(message) {
       message = new Date() + ' ' + message;
@@ -68,9 +68,7 @@ app.config(function($provide) {
 });
 
 app.controller('AppController', function($q, $log, DriveScannerService, SelectionStateService, ImageWriterService) {
-  'use strict';
-
-  var self = this;
+  let self = this;
   this.selection = SelectionStateService;
   this.writer = ImageWriterService;
   this.scanner = DriveScannerService;
@@ -86,14 +84,14 @@ app.controller('AppController', function($q, $log, DriveScannerService, Selectio
       // otherwise the drive is selected while the drive step is disabled
       // which looks very weird.
       if (drives.length === 1 && self.selection.hasImage()) {
-        var drive = _.first(drives);
+        const drive = _.first(drives);
 
         // Do not autoselect the same drive over and over again
         // and fill the logs unnecessary.
         // `angular.equals` is used instead of `_.isEqual` to
         // cope with `$$hashKey`.
         if (!angular.equals(self.selection.getDrive(), drive)) {
-          $log.debug('Autoselecting drive: ' + drive.device);
+          $log.debug(`Autoselecting drive: ${drive.device}`);
           self.selectDrive(drive);
         }
 
@@ -117,13 +115,13 @@ app.controller('AppController', function($q, $log, DriveScannerService, Selectio
   this.selectImage = function() {
     return $q.when(dialog.selectImage()).then(function(image) {
       self.selection.setImage(image);
-      $log.debug('Image selected: ' + image);
+      $log.debug(`Image selected: ${image}`);
     });
   };
 
   this.selectDrive = function(drive) {
     self.selection.setDrive(drive);
-    $log.debug('Drive selected: ' + drive.device);
+    $log.debug(`Drive selected: ${drive.device}`);
   };
 
   this.reselectImage = function() {
@@ -155,7 +153,7 @@ app.controller('AppController', function($q, $log, DriveScannerService, Selectio
     // otherwise Windows throws EPERM
     self.scanner.stop();
 
-    $log.debug('Burning ' + image + ' to ' + drive.device);
+    $log.debug(`Burning ${image} to ${drive.device}`);
     return self.writer.burn(image, drive).then(function() {
       $log.debug('Done!');
     }).catch(dialog.showError);
diff --git a/lib/browser/modules/drive-scanner.js b/lib/browser/modules/drive-scanner.js
index dca53c09..b2d11337 100644
--- a/lib/browser/modules/drive-scanner.js
+++ b/lib/browser/modules/drive-scanner.js
@@ -14,14 +14,16 @@
  * limitations under the License.
  */
 
+'use strict';
+
 /**
  * @module ResinEtcher.drive-scanner
  */
 
-var angular = require('angular');
-var _ = require('lodash');
-var EventEmitter = require('events').EventEmitter;
-var electron = require('electron');
+const angular = require('angular');
+const _ = require('lodash');
+const EventEmitter = require('events').EventEmitter;
+const electron = require('electron');
 
 if (window.mocha) {
   var path = require('path');
@@ -33,12 +35,10 @@ if (window.mocha) {
   var dialog = electron.remote.require('./src/dialog');
 }
 
-var driveScanner = angular.module('ResinEtcher.drive-scanner', []);
+const driveScanner = angular.module('ResinEtcher.drive-scanner', []);
 
 driveScanner.service('DriveScannerRefreshService', function($interval, $timeout) {
-  'use strict';
-
-  var interval = null;
+  let interval = null;
 
   /**
    * @summary Run a function every certain milliseconds
@@ -80,9 +80,7 @@ driveScanner.service('DriveScannerRefreshService', function($interval, $timeout)
 });
 
 driveScanner.service('DriveScannerService', function($q, DriveScannerRefreshService) {
-  'use strict';
-
-  var self = this;
+  let self = this;
 
   /**
    * @summary List of available drives
@@ -160,14 +158,14 @@ driveScanner.service('DriveScannerService', function($q, DriveScannerRefreshServ
    * @returns {EventEmitter} event emitter instance
    *
    * @example
-   * var emitter = DriveScannerService.start(2000);
+   * const emitter = DriveScannerService.start(2000);
    *
    * emitter.on('scan', function(drives) {
    *   console.log(drives);
    * });
    */
   this.start = function(ms) {
-    var emitter = new EventEmitter();
+    let emitter = new EventEmitter();
 
     DriveScannerRefreshService.every(function() {
       return self.scan().then(function(drives) {
diff --git a/lib/browser/modules/image-writer.js b/lib/browser/modules/image-writer.js
index 5a6c7197..9b6f9363 100644
--- a/lib/browser/modules/image-writer.js
+++ b/lib/browser/modules/image-writer.js
@@ -14,12 +14,14 @@
  * limitations under the License.
  */
 
+'use strict';
+
 /**
  * @module ResinEtcher.image-writer
  */
 
-var angular = require('angular');
-var electron = require('electron');
+const angular = require('angular');
+const electron = require('electron');
 
 if (window.mocha) {
   var writer = electron.remote.require(require('path').join(__dirname, '..', '..', 'src', 'writer'));
@@ -27,13 +29,11 @@ if (window.mocha) {
   var writer = electron.remote.require('./src/writer');
 }
 
-var imageWriter = angular.module('ResinEtcher.image-writer', []);
+const imageWriter = angular.module('ResinEtcher.image-writer', []);
 
 imageWriter.service('ImageWriterService', function($q, $timeout, $log) {
-  'use strict';
-
-  var self = this;
-  var burning = false;
+  let self = this;
+  let burning = false;
 
   /*
    * @summary Progress state
@@ -80,7 +80,7 @@ imageWriter.service('ImageWriterService', function($q, $timeout, $log) {
       // Transform bytes to megabytes preserving only two decimal places
       self.state.speed = Math.floor(state.speed / 1e+6 * 100) / 100 || 0;
 
-      $log.debug('Progress: ' + self.state.progress + '% at ' + self.state.speed + ' MB/s');
+      $log.debug(`Progress: ${self.state.progress}% at ${self.state.speed} MB/s`);
     });
 
   };
diff --git a/lib/browser/modules/path.js b/lib/browser/modules/path.js
index 05fe64d7..2450e92e 100644
--- a/lib/browser/modules/path.js
+++ b/lib/browser/modules/path.js
@@ -14,17 +14,18 @@
  * limitations under the License.
  */
 
+'use strict';
+
 /**
  * @module ResinEtcher.path
  */
 
-var angular = require('angular');
-var path = require('path');
+const angular = require('angular');
+const path = require('path');
 
-var pathModule = angular.module('ResinEtcher.path', []);
+const pathModule = angular.module('ResinEtcher.path', []);
 
 pathModule.filter('basename', function() {
-  'use strict';
 
   /**
    * @summary Get the basename of a path
diff --git a/lib/browser/modules/selection-state.js b/lib/browser/modules/selection-state.js
index 9f287500..80c5b524 100644
--- a/lib/browser/modules/selection-state.js
+++ b/lib/browser/modules/selection-state.js
@@ -14,25 +14,25 @@
  * limitations under the License.
  */
 
+'use strict';
+
 /**
  * @module ResinEtcher.selection-state
  */
 
-var _ = require('lodash');
-var angular = require('angular');
-var selectionState = angular.module('ResinEtcher.selection-state', []);
+const _ = require('lodash');
+const angular = require('angular');
+const selectionState = angular.module('ResinEtcher.selection-state', []);
 
 selectionState.service('SelectionStateService', function() {
-  'use strict';
-
-  var self = this;
+  let self = this;
 
   /**
    * @summary Selection state
    * @type Object
    * @private
    */
-  var selection = {};
+  let selection = {};
 
   /**
    * @summary Set a drive
@@ -72,7 +72,7 @@ selectionState.service('SelectionStateService', function() {
    * @returns {Object} drive
    *
    * @example
-   * var drive = SelectionStateService.getDrive();
+   * const drive = SelectionStateService.getDrive();
    */
   this.getDrive = function() {
     return selection.drive;
@@ -86,7 +86,7 @@ selectionState.service('SelectionStateService', function() {
    * @returns {String} image
    *
    * @example
-   * var image = SelectionStateService.getImage();
+   * const image = SelectionStateService.getImage();
    */
   this.getImage = function() {
     return selection.image;
@@ -132,9 +132,7 @@ selectionState.service('SelectionStateService', function() {
    * @example
    * SelectionStateService.removeDrive();
    */
-  this.removeDrive = function() {
-    self.setDrive(undefined);
-  };
+  this.removeDrive = _.partial(self.setDrive, undefined);
 
   /**
    * @summary Remove image
@@ -144,9 +142,7 @@ selectionState.service('SelectionStateService', function() {
    * @example
    * SelectionStateService.removeImage();
    */
-  this.removeImage = function() {
-    self.setImage(undefined);
-  };
+  this.removeImage = _.partial(self.setImage, undefined);
 
   /**
    * @summary Clear selections
diff --git a/lib/components/hero-badge.html b/lib/components/hero-badge.html
index 6020ec8d..017a68fb 100644
--- a/lib/components/hero-badge.html
+++ b/lib/components/hero-badge.html
@@ -19,6 +19,6 @@
   </template>
 
   <script>
-    Polymer({ is: "hero-badge" });
+    Polymer({ is: 'hero-badge' });
   </script>
 </dom-module>
diff --git a/lib/components/hero-button.html b/lib/components/hero-button.html
index 541c9d33..002c66ae 100644
--- a/lib/components/hero-button.html
+++ b/lib/components/hero-button.html
@@ -40,7 +40,7 @@
 
   <script>
     Polymer({
-      is: "hero-button",
+      is: 'hero-button',
       properties: {
         disabled: {
           type: String
@@ -51,7 +51,9 @@
         }
       },
       ready: function() {
-        this.querySelector('.btn').className += ' btn-' + this.type;
+        'use strict';
+
+        this.querySelector('.btn').className += ` btn-${this.type}`;
       }
     });
   </script>
diff --git a/lib/components/hero-caption.html b/lib/components/hero-caption.html
index c22d25ec..082f259c 100644
--- a/lib/components/hero-caption.html
+++ b/lib/components/hero-caption.html
@@ -15,6 +15,6 @@
   </template>
 
   <script>
-    Polymer({ is: "hero-caption" });
+    Polymer({ is: 'hero-caption' });
   </script>
 </dom-module>
diff --git a/lib/components/hero-icon.html b/lib/components/hero-icon.html
index a2956846..49a7fd61 100644
--- a/lib/components/hero-icon.html
+++ b/lib/components/hero-icon.html
@@ -20,11 +20,11 @@
   </template>
 
   <script>
-    var fs = require('fs');
-    var path = require('path');
+    const fs = require('fs');
+    const path = require('path');
 
     Polymer({
-      is: "hero-icon",
+      is: 'hero-icon',
       properties: {
         path: {
           type: String
@@ -40,9 +40,11 @@
         }
       },
       ready: function() {
-        var iconElement = this.querySelector('.icon');
-        var imagePath = path.join(__dirname, this.path);
-        var contents = fs.readFileSync(imagePath, {
+        'use strict';
+
+        const iconElement = this.querySelector('.icon');
+        const imagePath = path.join(__dirname, this.path);
+        const contents = fs.readFileSync(imagePath, {
           encoding: 'utf8'
         });
 
diff --git a/lib/components/hero-progress-button.html b/lib/components/hero-progress-button.html
index b13e4520..37ae8eec 100644
--- a/lib/components/hero-progress-button.html
+++ b/lib/components/hero-progress-button.html
@@ -37,7 +37,7 @@
 
   <script>
     Polymer({
-      is: "hero-progress-button",
+      is: 'hero-progress-button',
       properties: {
         disabled: {
           type: String
@@ -49,10 +49,14 @@
         }
       },
       setProgress: function(percentage) {
-        var bar = this.querySelector('.bar');
+        'use strict';
+
+        let bar = this.querySelector('.bar');
         bar.style.width = percentage + '%';
       },
       ready: function() {
+        'use strict';
+
         this.setProgress(this.percentage);
         this.addEventListener('percentage-changed', function(event) {
           this.setProgress(event.detail.value);
diff --git a/lib/components/hero-tick.html b/lib/components/hero-tick.html
index 52ad7f72..99a58eb3 100644
--- a/lib/components/hero-tick.html
+++ b/lib/components/hero-tick.html
@@ -24,21 +24,23 @@
 
   <script>
     Polymer({
-      is: "hero-tick",
+      is: 'hero-tick',
       properties: {
         type: {
           type: String
         }
       },
       ready: function() {
-        var glyphicon = this.querySelector('.glyphicon');
+        'use strict';
+
+        let glyphicon = this.querySelector('.glyphicon');
 
         if (this.type === 'success') {
           glyphicon.className += ' glyphicon-ok';
         } else if (this.type === 'error') {
           glyphicon.className += ' glyphicon-remove';
         } else {
-          throw new Error('Unknown hero-tick type: ' + this.state);
+          throw new Error(`Unknown hero-tick type: ${this.state}`);
         }
       }
     });
diff --git a/lib/elevate.js b/lib/elevate.js
index 250fd423..0f61dba6 100644
--- a/lib/elevate.js
+++ b/lib/elevate.js
@@ -14,16 +14,16 @@
  * limitations under the License.
  */
 
-var _ = require('lodash');
-var electron = require('electron');
-var isElevated = require('is-elevated');
-var sudoPrompt = require('sudo-prompt');
-var os = require('os');
-var platform = os.platform();
+'use strict';
+
+const _ = require('lodash');
+const electron = require('electron');
+const isElevated = require('is-elevated');
+const sudoPrompt = require('sudo-prompt');
+const os = require('os');
+const platform = os.platform();
 
 exports.require = function(app, callback) {
-  'use strict';
-
   isElevated(function(error, elevated) {
     if (error) {
       return callback(error);
@@ -52,7 +52,7 @@ exports.require = function(app, callback) {
           process.exit(0);
         });
       } else if (platform === 'win32') {
-        var elevator = require('elevator');
+        const elevator = require('elevator');
 
         elevator.execute(process.argv, {}, function(error) {
           if (error) {
diff --git a/lib/etcher.js b/lib/etcher.js
index 5bbadb72..64a5abf1 100644
--- a/lib/etcher.js
+++ b/lib/etcher.js
@@ -14,15 +14,16 @@
  * limitations under the License.
  */
 
-var electron = require('electron');
-var path = require('path');
-var elevate = require('./elevate');
-var mainWindow = null;
+'use strict';
+
+const electron = require('electron');
+const path = require('path');
+const elevate = require('./elevate');
+let mainWindow = null;
 
 electron.app.on('window-all-closed', electron.app.quit);
 
 electron.app.on('ready', function() {
-  'use strict';
 
   // No menu bar
   electron.Menu.setApplicationMenu(null);
@@ -49,7 +50,7 @@ electron.app.on('ready', function() {
       mainWindow.webContents.openDevTools();
     });
 
-    mainWindow.loadURL('file://' + path.join(__dirname, 'index.html'));
+    mainWindow.loadURL(`file://${path.join(__dirname, 'index.html')}`);
   });
 });
 
diff --git a/lib/src/dialog.js b/lib/src/dialog.js
index 5b90a81e..9dc088c0 100644
--- a/lib/src/dialog.js
+++ b/lib/src/dialog.js
@@ -14,9 +14,10 @@
  * limitations under the License.
  */
 
-var electron = require('electron');
-var Bluebird = require('bluebird');
-var _ = require('lodash');
+'use strict';
+
+const electron = require('electron');
+const Bluebird = require('bluebird');
 
 /**
  * @summary Open an image selection dialog
@@ -35,8 +36,6 @@ var _ = require('lodash');
  * });
  */
 exports.selectImage = function() {
-  'use strict';
-
   return new Bluebird(function(resolve) {
     electron.dialog.showOpenDialog({
       properties: [ 'openFile' ],
@@ -49,10 +48,8 @@ exports.selectImage = function() {
           ]
         }
       ]
-    }, function(file) {
-      return resolve(_.first(file));
-    });
-  });
+    }, resolve);
+  }).get(0);
 };
 
 /**
@@ -66,7 +63,5 @@ exports.selectImage = function() {
  * dialog.showError(new Error('Foo Bar'));
  */
 exports.showError = function(error) {
-  'use strict';
-
   electron.dialog.showErrorBox(error.message, error.stack || '');
 };
diff --git a/lib/src/drives.js b/lib/src/drives.js
index 4750c33e..ae9b651d 100644
--- a/lib/src/drives.js
+++ b/lib/src/drives.js
@@ -14,8 +14,10 @@
  * limitations under the License.
  */
 
-var Bluebird = require('bluebird');
-var drivelist = Bluebird.promisifyAll(require('drivelist'));
+'use strict';
+
+const Bluebird = require('bluebird');
+const drivelist = Bluebird.promisifyAll(require('drivelist'));
 
 /**
  * @summary List all available removable drives
@@ -33,8 +35,6 @@ var drivelist = Bluebird.promisifyAll(require('drivelist'));
  * });
  */
 exports.listRemovable = function() {
-  'use strict';
-
   return drivelist.listAsync().then(function(drives) {
     return drives.filter(function(drive) {
       return !drive.system;
diff --git a/lib/src/writer.js b/lib/src/writer.js
index 288fa183..13066245 100644
--- a/lib/src/writer.js
+++ b/lib/src/writer.js
@@ -14,12 +14,14 @@
  * limitations under the License.
  */
 
-var imageWrite = require('resin-image-write');
-var Bluebird = require('bluebird');
-var umount = Bluebird.promisifyAll(require('umount'));
-var fs = require('fs');
-var os = require('os');
-var isWindows = os.platform() === 'win32';
+'use strict';
+
+const imageWrite = require('resin-image-write');
+const Bluebird = require('bluebird');
+const umount = Bluebird.promisifyAll(require('umount'));
+const fs = require('fs');
+const os = require('os');
+const isWindows = os.platform() === 'win32';
 
 if (isWindows) {
   var removedrive = Bluebird.promisifyAll(require('removedrive'));
@@ -38,12 +40,10 @@ if (isWindows) {
  * @returns {ReadableStream} image stream
  *
  * @example
- * var stream = writer.getImageStream('foo/bar/baz.img');
+ * const stream = writer.getImageStream('foo/bar/baz.img');
  */
 exports.getImageStream = function(image) {
-  'use strict';
-
-  var stream = fs.createReadStream(image);
+  let stream = fs.createReadStream(image);
   stream.length = fs.statSync(image).size;
   return stream;
 };
@@ -73,10 +73,8 @@ exports.getImageStream = function(image) {
  * });
  */
 exports.writeImage = function(image, drive, onProgress) {
-  'use strict';
-
   return umount.umountAsync(drive.device).then(function() {
-    var stream = exports.getImageStream(image);
+    let stream = exports.getImageStream(image);
     return imageWrite.write(drive.device, stream);
   }).then(function(writer) {
     return new Bluebird(function(resolve, reject) {
diff --git a/tests/browser/modules/drive-scanner.spec.js b/tests/browser/modules/drive-scanner.spec.js
index 8f4c1dc4..12ab6ffc 100644
--- a/tests/browser/modules/drive-scanner.spec.js
+++ b/tests/browser/modules/drive-scanner.spec.js
@@ -1,18 +1,19 @@
-var m = require('mochainon');
-var angular = require('angular');
+'use strict';
+
+const m = require('mochainon');
+const angular = require('angular');
 require('angular-mocks');
 require('../../../lib/browser/modules/drive-scanner');
 
 describe('Browser: DriveScanner', function() {
-  'use strict';
 
   beforeEach(angular.mock.module('ResinEtcher.drive-scanner'));
 
   describe('DriveScannerRefreshService', function() {
 
-    var DriveScannerRefreshService;
-    var $interval;
-    var $timeout;
+    let DriveScannerRefreshService;
+    let $interval;
+    let $timeout;
 
     beforeEach(angular.mock.inject(function(_$interval_, _$timeout_, _DriveScannerRefreshService_) {
       $interval = _$interval_;
@@ -23,7 +24,7 @@ describe('Browser: DriveScanner', function() {
     describe('.every()', function() {
 
       it('should call the function right away', function() {
-        var spy = m.sinon.spy();
+        const spy = m.sinon.spy();
         DriveScannerRefreshService.every(spy, 1000);
         $timeout.flush();
         DriveScannerRefreshService.stop();
@@ -31,7 +32,7 @@ describe('Browser: DriveScanner', function() {
       });
 
       it('should call the function in an interval', function() {
-        var spy = m.sinon.spy();
+        const spy = m.sinon.spy();
         DriveScannerRefreshService.every(spy, 100);
         $timeout.flush();
 
@@ -48,10 +49,10 @@ describe('Browser: DriveScanner', function() {
 
   describe('DriveScannerService', function() {
 
-    var $interval;
-    var $timeout;
-    var $q;
-    var DriveScannerService;
+    let $interval;
+    let $timeout;
+    let $q;
+    let DriveScannerService;
 
     beforeEach(angular.mock.inject(function(_$interval_, _$timeout_, _$q_, _DriveScannerService_) {
       $interval = _$interval_;
@@ -69,7 +70,7 @@ describe('Browser: DriveScanner', function() {
       describe('.hasAvailableDrives()', function() {
 
         it('should return false', function() {
-          var hasDrives = DriveScannerService.hasAvailableDrives();
+          const hasDrives = DriveScannerService.hasAvailableDrives();
           m.chai.expect(hasDrives).to.be.false;
         });
 
@@ -78,7 +79,7 @@ describe('Browser: DriveScanner', function() {
       describe('.setDrives()', function() {
 
         it('should be able to set drives', function() {
-          var drives = [
+          const drives = [
             {
               device: '/dev/sdb',
               description: 'Foo',
@@ -122,7 +123,7 @@ describe('Browser: DriveScanner', function() {
       describe('.hasAvailableDrives()', function() {
 
         it('should return true', function() {
-          var hasDrives = DriveScannerService.hasAvailableDrives();
+          const hasDrives = DriveScannerService.hasAvailableDrives();
           m.chai.expect(hasDrives).to.be.true;
         });
 
@@ -184,8 +185,8 @@ describe('Browser: DriveScanner', function() {
       describe('.start()', function() {
 
         it('should emit a `scan` event with the drives', function() {
-          var emitter = DriveScannerService.start(2000);
-          var scanSpy = m.sinon.spy();
+          const emitter = DriveScannerService.start(2000);
+          const scanSpy = m.sinon.spy();
           emitter.on('scan', scanSpy);
           $timeout.flush();
           $interval.flush(1000);
diff --git a/tests/browser/modules/image-writer.spec.js b/tests/browser/modules/image-writer.spec.js
index 964299c8..04676da2 100644
--- a/tests/browser/modules/image-writer.spec.js
+++ b/tests/browser/modules/image-writer.spec.js
@@ -1,19 +1,20 @@
-var m = require('mochainon');
-var angular = require('angular');
+'use strict';
+
+const m = require('mochainon');
+const angular = require('angular');
 require('angular-mocks');
 require('../../../lib/browser/modules/image-writer');
 
 describe('Browser: ImageWriter', function() {
-  'use strict';
 
   beforeEach(angular.mock.module('ResinEtcher.image-writer'));
 
   describe('ImageWriterService', function() {
 
-    var $q;
-    var $timeout;
-    var $rootScope;
-    var ImageWriterService;
+    let $q;
+    let $timeout;
+    let $rootScope;
+    let ImageWriterService;
 
     beforeEach(angular.mock.inject(function(_$q_, _$timeout_, _$rootScope_, _ImageWriterService_) {
       $q = _$q_;
@@ -174,7 +175,7 @@ describe('Browser: ImageWriter', function() {
         });
 
         it('should be rejected with the error', function() {
-          var rejection;
+          let rejection;
           ImageWriterService.burn('foo.img', '/dev/disk2').catch(function(error) {
             rejection = error;
           });
diff --git a/tests/browser/modules/path.spec.js b/tests/browser/modules/path.spec.js
index 6ba2d31e..0eeb467c 100644
--- a/tests/browser/modules/path.spec.js
+++ b/tests/browser/modules/path.spec.js
@@ -1,25 +1,26 @@
-var m = require('mochainon');
-var angular = require('angular');
-var os = require('os');
+'use strict';
+
+const m = require('mochainon');
+const angular = require('angular');
+const os = require('os');
 require('angular-mocks');
 require('../../../lib/browser/modules/path');
 
 describe('Browser: Path', function() {
-  'use strict';
 
   beforeEach(angular.mock.module('ResinEtcher.path'));
 
   describe('BasenameFilter', function() {
 
-    var basenameFilter;
+    let basenameFilter;
 
     beforeEach(angular.mock.inject(function(_basenameFilter_) {
       basenameFilter = _basenameFilter_;
     }));
 
     it('should return the basename', function() {
-      var isWindows = os.platform() === 'win32';
-      var basename;
+      const isWindows = os.platform() === 'win32';
+      let basename;
 
       if (isWindows) {
         basename = basenameFilter('C:\\Users\\jviotti\\foo.img');
diff --git a/tests/browser/modules/selection-state.spec.js b/tests/browser/modules/selection-state.spec.js
index 85a293c4..abdacfe5 100644
--- a/tests/browser/modules/selection-state.spec.js
+++ b/tests/browser/modules/selection-state.spec.js
@@ -1,16 +1,17 @@
-var m = require('mochainon');
-var angular = require('angular');
+'use strict';
+
+const m = require('mochainon');
+const angular = require('angular');
 require('angular-mocks');
 require('../../../lib/browser/modules/selection-state');
 
 describe('Browser: SelectionState', function() {
-  'use strict';
 
   beforeEach(angular.mock.module('ResinEtcher.selection-state'));
 
   describe('SelectionStateService', function() {
 
-    var SelectionStateService;
+    let SelectionStateService;
 
     beforeEach(angular.mock.inject(function(_SelectionStateService_) {
       SelectionStateService = _SelectionStateService_;
@@ -23,22 +24,22 @@ describe('Browser: SelectionState', function() {
       });
 
       it('getDrive() should return undefined', function() {
-        var drive = SelectionStateService.getDrive();
+        const drive = SelectionStateService.getDrive();
         m.chai.expect(drive).to.be.undefined;
       });
 
       it('getImage() should return undefined', function() {
-        var image = SelectionStateService.getImage();
+        const image = SelectionStateService.getImage();
         m.chai.expect(image).to.be.undefined;
       });
 
       it('hasDrive() should return false', function() {
-        var hasDrive = SelectionStateService.hasDrive();
+        const hasDrive = SelectionStateService.hasDrive();
         m.chai.expect(hasDrive).to.be.false;
       });
 
       it('hasImage() should return false', function() {
-        var hasImage = SelectionStateService.hasImage();
+        const hasImage = SelectionStateService.hasImage();
         m.chai.expect(hasImage).to.be.false;
       });
 
@@ -53,7 +54,7 @@ describe('Browser: SelectionState', function() {
       describe('.getDrive()', function() {
 
         it('should return the drive', function() {
-          var drive = SelectionStateService.getDrive();
+          const drive = SelectionStateService.getDrive();
           m.chai.expect(drive).to.equal('/dev/disk2');
         });
 
@@ -62,7 +63,7 @@ describe('Browser: SelectionState', function() {
       describe('.hasDrive()', function() {
 
         it('should return true', function() {
-          var hasDrive = SelectionStateService.hasDrive();
+          const hasDrive = SelectionStateService.hasDrive();
           m.chai.expect(hasDrive).to.be.true;
         });
 
@@ -72,7 +73,7 @@ describe('Browser: SelectionState', function() {
 
         it('should override the drive', function() {
           SelectionStateService.setDrive('/dev/disk5');
-          var drive = SelectionStateService.getDrive();
+          const drive = SelectionStateService.getDrive();
           m.chai.expect(drive).to.equal('/dev/disk5');
         });
 
@@ -82,7 +83,7 @@ describe('Browser: SelectionState', function() {
 
         it('should clear the drive', function() {
           SelectionStateService.removeDrive();
-          var drive = SelectionStateService.getDrive();
+          const drive = SelectionStateService.getDrive();
           m.chai.expect(drive).to.be.undefined;
         });
 
@@ -96,7 +97,7 @@ describe('Browser: SelectionState', function() {
 
         it('should be able to set a drive', function() {
           SelectionStateService.setDrive('/dev/disk5');
-          var drive = SelectionStateService.getDrive();
+          const drive = SelectionStateService.getDrive();
           m.chai.expect(drive).to.equal('/dev/disk5');
         });
 
@@ -113,7 +114,7 @@ describe('Browser: SelectionState', function() {
       describe('.getImage()', function() {
 
         it('should return the image', function() {
-          var image = SelectionStateService.getImage();
+          const image = SelectionStateService.getImage();
           m.chai.expect(image).to.equal('foo.img');
         });
 
@@ -122,7 +123,7 @@ describe('Browser: SelectionState', function() {
       describe('.hasImage()', function() {
 
         it('should return true', function() {
-          var hasImage = SelectionStateService.hasImage();
+          const hasImage = SelectionStateService.hasImage();
           m.chai.expect(hasImage).to.be.true;
         });
 
@@ -132,7 +133,7 @@ describe('Browser: SelectionState', function() {
 
         it('should override the image', function() {
           SelectionStateService.setImage('bar.img');
-          var image = SelectionStateService.getImage();
+          const image = SelectionStateService.getImage();
           m.chai.expect(image).to.equal('bar.img');
         });
 
@@ -142,7 +143,7 @@ describe('Browser: SelectionState', function() {
 
         it('should clear the image', function() {
           SelectionStateService.removeImage();
-          var image = SelectionStateService.getImage();
+          const image = SelectionStateService.getImage();
           m.chai.expect(image).to.be.undefined;
         });
 
@@ -156,7 +157,7 @@ describe('Browser: SelectionState', function() {
 
         it('should be able to set an image', function() {
           SelectionStateService.setImage('foo.img');
-          var image = SelectionStateService.getImage();
+          const image = SelectionStateService.getImage();
           m.chai.expect(image).to.equal('foo.img');
         });
 
@@ -194,22 +195,22 @@ describe('Browser: SelectionState', function() {
         });
 
         it('getDrive() should return undefined', function() {
-          var drive = SelectionStateService.getDrive();
+          const drive = SelectionStateService.getDrive();
           m.chai.expect(drive).to.be.undefined;
         });
 
         it('getImage() should return the image', function() {
-          var image = SelectionStateService.getImage();
+          const image = SelectionStateService.getImage();
           m.chai.expect(image).to.equal('foo.img');
         });
 
         it('hasDrive() should return false', function() {
-          var hasDrive = SelectionStateService.hasDrive();
+          const hasDrive = SelectionStateService.hasDrive();
           m.chai.expect(hasDrive).to.be.false;
         });
 
         it('hasImage() should return true', function() {
-          var hasImage = SelectionStateService.hasImage();
+          const hasImage = SelectionStateService.hasImage();
           m.chai.expect(hasImage).to.be.true;
         });
 
diff --git a/tests/src/dialog.spec.js b/tests/src/dialog.spec.js
index be2bb9e2..d88d7924 100644
--- a/tests/src/dialog.spec.js
+++ b/tests/src/dialog.spec.js
@@ -1,9 +1,10 @@
-var m = require('mochainon');
-var electron = require('electron');
-var dialog = require('../../lib/src/dialog');
+'use strict';
+
+const m = require('mochainon');
+const electron = require('electron');
+const dialog = require('../../lib/src/dialog');
 
 describe('Dialog:', function() {
-  'use strict';
 
   describe('.selectImage()', function() {
 
@@ -19,7 +20,7 @@ describe('Dialog:', function() {
       });
 
       it('should eventually equal the file', function() {
-        var promise = dialog.selectImage();
+        const promise = dialog.selectImage();
         m.chai.expect(promise).to.eventually.equal('foo/bar');
       });
 
diff --git a/tests/src/drives.spec.js b/tests/src/drives.spec.js
index f56c9c65..53f0a48e 100644
--- a/tests/src/drives.spec.js
+++ b/tests/src/drives.spec.js
@@ -1,10 +1,11 @@
-var m = require('mochainon');
-var Bluebird = require('bluebird');
-var drivelist = require('drivelist');
-var drives = require('../../lib/src/drives');
+'use strict';
+
+const m = require('mochainon');
+const Bluebird = require('bluebird');
+const drivelist = require('drivelist');
+const drives = require('../../lib/src/drives');
 
 describe('Drives:', function() {
-  'use strict';
 
   describe('.listRemovable()', function() {
 
@@ -20,7 +21,7 @@ describe('Drives:', function() {
       });
 
       it('should eventually equal an empty array', function() {
-        var promise = drives.listRemovable();
+        const promise = drives.listRemovable();
         m.chai.expect(promise).to.eventually.become([]);
       });
 
@@ -48,7 +49,7 @@ describe('Drives:', function() {
       });
 
       it('should eventually equal an empty array', function() {
-        var promise = drives.listRemovable();
+        const promise = drives.listRemovable();
         m.chai.expect(promise).to.eventually.become([]);
       });
 
@@ -90,7 +91,7 @@ describe('Drives:', function() {
       });
 
       it('should eventually become the removable drives', function() {
-        var promise = drives.listRemovable();
+        const promise = drives.listRemovable();
         m.chai.expect(promise).to.eventually.become([
           {
             device: '/dev/sdb',
@@ -123,7 +124,7 @@ describe('Drives:', function() {
       });
 
       it('should be rejected with the error', function() {
-        var promise = drives.listRemovable();
+        const promise = drives.listRemovable();
         m.chai.expect(promise).to.be.rejectedWith('scan error');
       });
 
diff --git a/tests/src/writer.spec.js b/tests/src/writer.spec.js
index 1b351bd4..7432c4ca 100644
--- a/tests/src/writer.spec.js
+++ b/tests/src/writer.spec.js
@@ -1,11 +1,12 @@
-var m = require('mochainon');
-var ReadableStream = require('stream').Readable;
-var path = require('path');
-var umount = require('umount');
-var writer = require('../../lib/src/writer');
+'use strict';
+
+const m = require('mochainon');
+const ReadableStream = require('stream').Readable;
+const path = require('path');
+const umount = require('umount');
+const writer = require('../../lib/src/writer');
 
 describe('Writer:', function() {
-  'use strict';
 
   describe('.getImageStream()', function() {
 
@@ -16,12 +17,12 @@ describe('Writer:', function() {
       });
 
       it('should return a readable stream', function() {
-        var stream = writer.getImageStream(this.image);
+        const stream = writer.getImageStream(this.image);
         m.chai.expect(stream).to.be.an.instanceof(ReadableStream);
       });
 
       it('should append a .length property with the correct size', function() {
-        var stream = writer.getImageStream(this.image);
+        const stream = writer.getImageStream(this.image);
         m.chai.expect(stream.length).to.equal(2097152);
       });