diff --git a/.eslintignore b/.eslintignore
new file mode 100644
index 0000000..1521c8b
--- /dev/null
+++ b/.eslintignore
@@ -0,0 +1 @@
+dist
diff --git a/dist/image-editor.js b/dist/image-editor.js
index 10adb22..0bc914c 100644
--- a/dist/image-editor.js
+++ b/dist/image-editor.js
@@ -614,7 +614,6 @@ var DragHandle = function (handler) {
   var _currentAxis;
   var _dragHandle;
   var _clickHandle = false;
-  var _movedHandle;
 
   // Event declarations
   var events = {
@@ -638,7 +637,6 @@ var DragHandle = function (handler) {
       }
 
       _dragHandle = false;
-      _movedHandle = false;
       _currentAxis = null;
       util.MouseMetrics.deletePreviousMouseData();
       handler.canvas.getImage().trigger('mouseup');
@@ -660,7 +658,6 @@ var DragHandle = function (handler) {
         y: 'movementY' in e.e ? e.e.movementY : (previousMouseData.y ? pageY - previousMouseData.y : 0)
       };
       util.MouseMetrics.setPreviousMouseData({x: pageX, y: pageY});
-      _movedHandle = true;
 
       if (_currentAxis === 'x') {
         handler.canvas.getImage().left -= movement.x;
@@ -1486,7 +1483,8 @@ function MirrorHandler(img) {
      * @return {MirrorHandler}
      */
   this.set = function(checked) {
-    _mirrored = (img.flipX = checked) ? 1 : 0;
+    img.flipX = checked;
+    _mirrored = checked ? 1 : 0;
     img.setCoords().canvas.renderAll();
 
     return this;
@@ -1656,7 +1654,7 @@ function TextButton(id, text, settings, isActive) {
 
   fabric.Group.call(this);
 
-  var __active = isActive || false;
+  this.__active = isActive || false;
   var _callback = null;
   var _rect = null;
   var _text = null;
diff --git a/gulpfile.js b/gulpfile.js
index a5ceb3d..d914839 100644
--- a/gulpfile.js
+++ b/gulpfile.js
@@ -1,33 +1,54 @@
+'use strict';
+
 var gulp = require('gulp');
 var browserify = require('browserify');
 var buffer = require('vinyl-buffer');
 var rename = require('gulp-rename');
 var source = require('vinyl-source-stream');
-var jshint = require('gulp-jshint');
+var eslint = require('gulp-eslint');
 var qunit = require('gulp-qunit');
+var mkdirp = require('mkdirp');
+var del = require('del');
+var runSequence = require('run-sequence');
 
-gulp.task('build', function() {
+var outputPath = './dist';
+
+gulp.task('build', function (done) {
+  runSequence(
+    'clean-dist',
+    'create-dist',
+    'lint',
+    'compile',
+    done);
+});
+
+gulp.task('clean-dist', function () { return del(outputPath); });
+
+gulp.task('create-dist', function () { return mkdirp(outputPath); });
+
+gulp.task('compile', function() {
   return browserify('./src/main.js')
     .bundle()
     .pipe(source('main.js'))
     .pipe(buffer())
     .pipe(rename('image-editor.js'))
-    .pipe(gulp.dest('./dist'));
+    .pipe(gulp.dest(outputPath));
 });
 
-gulp.task('test', ['build'], function() {
+gulp.task('test', ['compile'], function() {
   return gulp.src('./test/index.html')
     .pipe(qunit({timeout: 1}));
 });
 
 gulp.task('lint', function() {
   return gulp.src(['./src/**/*.js', './test/unit/*.js'])
-    .pipe(jshint())
-    .pipe(jshint.reporter('default'));
+    .pipe(eslint())
+    .pipe(eslint.format())
+    .pipe(eslint.failAfterError());
 });
 
 gulp.task('watch', function() {
-  gulp.watch('./src/**/*.js', ['build']);
+  gulp.watch('./src/**/*.js', ['lint', 'compile']);
 });
 
-gulp.task('default', ['lint', 'build']);
+gulp.task('default', ['build']);
diff --git a/package-lock.json b/package-lock.json
index 205d4aa..f42eba7 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -119,6 +119,15 @@
       "dev": true,
       "optional": true
     },
+    "ansi-colors": {
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/ansi-colors/-/ansi-colors-1.1.0.tgz",
+      "integrity": "sha512-SFKX67auSNoVR38N3L+nvsPjOE0bybKTYbkf5tRvushrAPQ9V75huw0ZxBkKVeRU9kqH3d6HA4xTckbwZ4ixmA==",
+      "dev": true,
+      "requires": {
+        "ansi-wrap": "^0.1.0"
+      }
+    },
     "ansi-cyan": {
       "version": "0.1.1",
       "resolved": "https://registry.npmjs.org/ansi-cyan/-/ansi-cyan-0.1.1.tgz",
@@ -134,6 +143,15 @@
       "integrity": "sha512-cBhpre4ma+U0T1oM5fXg7Dy1Jw7zzwv7lt/GoCpr+hDQJoYnKVPLL4dCvSEFMmQurOQvSrwT7SL/DAlhBI97RQ==",
       "dev": true
     },
+    "ansi-gray": {
+      "version": "0.1.1",
+      "resolved": "https://registry.npmjs.org/ansi-gray/-/ansi-gray-0.1.1.tgz",
+      "integrity": "sha1-KWLPVOyXksSFEKPetSRDaGHvclE=",
+      "dev": true,
+      "requires": {
+        "ansi-wrap": "0.1.0"
+      }
+    },
     "ansi-red": {
       "version": "0.1.1",
       "resolved": "https://registry.npmjs.org/ansi-red/-/ansi-red-0.1.1.tgz",
@@ -195,9 +213,9 @@
       "dev": true
     },
     "arr-union": {
-      "version": "2.1.0",
-      "resolved": "https://registry.npmjs.org/arr-union/-/arr-union-2.1.0.tgz",
-      "integrity": "sha1-IPnqtexw9cfSFbEHexw5Fh0pLH0=",
+      "version": "3.1.0",
+      "resolved": "https://registry.npmjs.org/arr-union/-/arr-union-3.1.0.tgz",
+      "integrity": "sha1-45sJrqne+Gao8gbiiK9jkZuuOcQ=",
       "dev": true
     },
     "array-differ": {
@@ -236,6 +254,15 @@
       "integrity": "sha512-B1qMD3RBP7O8o0H2KbrXDyB0IccejMF15+87Lvlor12ONPRHP6gTjXMNkt/d3ZuOGbAe66hFmaCfECI24Ufp6w==",
       "dev": true
     },
+    "array-union": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/array-union/-/array-union-1.0.2.tgz",
+      "integrity": "sha1-mjRBDk9OPaI96jdb5b5w8kd47Dk=",
+      "dev": true,
+      "requires": {
+        "array-uniq": "^1.0.1"
+      }
+    },
     "array-uniq": {
       "version": "1.0.3",
       "resolved": "https://registry.npmjs.org/array-uniq/-/array-uniq-1.0.3.tgz",
@@ -909,6 +936,12 @@
       "integrity": "sha1-p9BVi9icQveV3UIyj3QIMcpTvCU=",
       "dev": true
     },
+    "color-support": {
+      "version": "1.1.3",
+      "resolved": "https://registry.npmjs.org/color-support/-/color-support-1.1.3.tgz",
+      "integrity": "sha512-qiBjkpbMLO/HL68y+lh4q0/O1MZFj2RX6X/KmMa3+gJD3z+WwI1ZzDHysvqHGS3mP6mznPckpXmw1nI9cJjyRg==",
+      "dev": true
+    },
     "colors": {
       "version": "1.0.3",
       "resolved": "https://registry.npmjs.org/colors/-/colors-1.0.3.tgz",
@@ -1215,6 +1248,20 @@
       "integrity": "sha1-yY2bzvdWdBiOEQlpFRGZ45sfppM=",
       "dev": true
     },
+    "del": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/del/-/del-3.0.0.tgz",
+      "integrity": "sha1-U+z2mf/LyzljdpGrE7rxYIGXZuU=",
+      "dev": true,
+      "requires": {
+        "globby": "^6.1.0",
+        "is-path-cwd": "^1.0.0",
+        "is-path-in-cwd": "^1.0.0",
+        "p-map": "^1.1.1",
+        "pify": "^3.0.0",
+        "rimraf": "^2.2.8"
+      }
+    },
     "delayed-stream": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/delayed-stream/-/delayed-stream-1.0.0.tgz",
@@ -1796,19 +1843,23 @@
       "dev": true
     },
     "extend-shallow": {
-      "version": "1.1.4",
-      "resolved": "https://registry.npmjs.org/extend-shallow/-/extend-shallow-1.1.4.tgz",
-      "integrity": "sha1-Gda/lN/AnXa6cR85uHLSH/TdkHE=",
+      "version": "3.0.2",
+      "resolved": "https://registry.npmjs.org/extend-shallow/-/extend-shallow-3.0.2.tgz",
+      "integrity": "sha1-Jqcarwc7OfshJxcnRhMcJwQCjbg=",
       "dev": true,
       "requires": {
-        "kind-of": "^1.1.0"
+        "assign-symbols": "^1.0.0",
+        "is-extendable": "^1.0.1"
       },
       "dependencies": {
-        "kind-of": {
-          "version": "1.1.0",
-          "resolved": "https://registry.npmjs.org/kind-of/-/kind-of-1.1.0.tgz",
-          "integrity": "sha1-FAo9LUGjbS78+pN3tiwk+ElaXEQ=",
-          "dev": true
+        "is-extendable": {
+          "version": "1.0.1",
+          "resolved": "https://registry.npmjs.org/is-extendable/-/is-extendable-1.0.1.tgz",
+          "integrity": "sha512-arnXMxT1hhoKo9k1LZdmlNyJdDDfy2v0fXjFlmok4+i8ul/6WlbVge9bhM74OpNPQPMGUToDtz+KXa1PneJxOA==",
+          "dev": true,
+          "requires": {
+            "is-plain-object": "^2.0.4"
+          }
         }
       }
     },
@@ -2307,6 +2358,33 @@
       "integrity": "sha512-WHq43gS+6ufNOEqlrDBxVEbb8ntfXrfAUU2ZOpCxrBdGKW3gyv8mCxAfIBD0DroPKGrJ2eSsXsLtY9MPntsyTw==",
       "dev": true
     },
+    "globby": {
+      "version": "6.1.0",
+      "resolved": "https://registry.npmjs.org/globby/-/globby-6.1.0.tgz",
+      "integrity": "sha1-9abXDoOV4hyFj7BInWTfAkJNUGw=",
+      "dev": true,
+      "requires": {
+        "array-union": "^1.0.1",
+        "glob": "^7.0.3",
+        "object-assign": "^4.0.1",
+        "pify": "^2.0.0",
+        "pinkie-promise": "^2.0.0"
+      },
+      "dependencies": {
+        "object-assign": {
+          "version": "4.1.1",
+          "resolved": "https://registry.npmjs.org/object-assign/-/object-assign-4.1.1.tgz",
+          "integrity": "sha1-IQmtx5ZYh8/AXLvUQsrIv7s2CGM=",
+          "dev": true
+        },
+        "pify": {
+          "version": "2.3.0",
+          "resolved": "https://registry.npmjs.org/pify/-/pify-2.3.0.tgz",
+          "integrity": "sha1-7RQaasBDqEnqWISY59yosVMw6Qw=",
+          "dev": true
+        }
+      }
+    },
     "globule": {
       "version": "0.1.0",
       "resolved": "https://registry.npmjs.org/globule/-/globule-0.1.0.tgz",
@@ -2392,24 +2470,28 @@
         "vinyl-fs": "^0.3.0"
       }
     },
-    "gulp-jshint": {
-      "version": "2.1.0",
-      "resolved": "https://registry.npmjs.org/gulp-jshint/-/gulp-jshint-2.1.0.tgz",
-      "integrity": "sha512-sP3NK8Y/1e58O0PH9t6s7DAr/lKDSUbIY207oWSeufM6/VclB7jJrIBcPCsyhrFTCDUl9DauePbt6VqP2vPM5w==",
+    "gulp-eslint": {
+      "version": "5.0.0",
+      "resolved": "https://registry.npmjs.org/gulp-eslint/-/gulp-eslint-5.0.0.tgz",
+      "integrity": "sha512-9GUqCqh85C7rP9120cpxXuZz2ayq3BZc85pCTuPJS03VQYxne0aWPIXWx6LSvsGPa3uRqtSO537vaugOh+5cXg==",
       "dev": true,
       "requires": {
-        "lodash": "^4.12.0",
-        "minimatch": "^3.0.3",
-        "plugin-error": "^0.1.2",
-        "rcloader": "^0.2.2",
-        "through2": "^2.0.0"
+        "eslint": "^5.0.1",
+        "fancy-log": "^1.3.2",
+        "plugin-error": "^1.0.1"
       },
       "dependencies": {
-        "lodash": {
-          "version": "4.17.11",
-          "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.11.tgz",
-          "integrity": "sha512-cQKh8igo5QUhZ7lg38DYWAxMvjSAKG0A8wGSVimP07SIUEK2UO+arSRKbRZWtelMtN5V0Hkwh5ryOto/SshYIg==",
-          "dev": true
+        "fancy-log": {
+          "version": "1.3.3",
+          "resolved": "https://registry.npmjs.org/fancy-log/-/fancy-log-1.3.3.tgz",
+          "integrity": "sha512-k9oEhlyc0FrVh25qYuSELjr8oxsCoc4/LEZfg2iJJrfEk/tZL9bCoJE47gqAvI2m/AUjluCS4+3I0eTx8n3AEw==",
+          "dev": true,
+          "requires": {
+            "ansi-gray": "^0.1.1",
+            "color-support": "^1.1.3",
+            "parse-node-version": "^1.0.0",
+            "time-stamp": "^1.0.0"
+          }
         }
       }
     },
@@ -3019,6 +3101,30 @@
         "kind-of": "^3.0.2"
       }
     },
+    "is-path-cwd": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/is-path-cwd/-/is-path-cwd-1.0.0.tgz",
+      "integrity": "sha1-0iXsIxMuie3Tj9p2dHLmLmXxEG0=",
+      "dev": true
+    },
+    "is-path-in-cwd": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/is-path-in-cwd/-/is-path-in-cwd-1.0.1.tgz",
+      "integrity": "sha512-FjV1RTW48E7CWM7eE/J2NJvAEEVektecDBVBE5Hh3nM1Jd0kvhHtX68Pr3xsDf857xt3Y4AkwVULK1Vku62aaQ==",
+      "dev": true,
+      "requires": {
+        "is-path-inside": "^1.0.0"
+      }
+    },
+    "is-path-inside": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/is-path-inside/-/is-path-inside-1.0.1.tgz",
+      "integrity": "sha1-jvW33lBDej/cprToZe96pVy0gDY=",
+      "dev": true,
+      "requires": {
+        "path-is-inside": "^1.0.1"
+      }
+    },
     "is-plain-object": {
       "version": "2.0.4",
       "resolved": "https://registry.npmjs.org/is-plain-object/-/is-plain-object-2.0.4.tgz",
@@ -3449,18 +3555,6 @@
       "integrity": "sha1-+6HEUkwZ7ppfgTa0YJ8BfPTe1pI=",
       "dev": true
     },
-    "lodash.assign": {
-      "version": "4.2.0",
-      "resolved": "https://registry.npmjs.org/lodash.assign/-/lodash.assign-4.2.0.tgz",
-      "integrity": "sha1-DZnzzNem0mHRm9rrkkUAXShYCOc=",
-      "dev": true
-    },
-    "lodash.clonedeep": {
-      "version": "4.5.0",
-      "resolved": "https://registry.npmjs.org/lodash.clonedeep/-/lodash.clonedeep-4.5.0.tgz",
-      "integrity": "sha1-4j8/nE+Pvd6HJSnBBxhXoIblzO8=",
-      "dev": true
-    },
     "lodash.escape": {
       "version": "3.2.0",
       "resolved": "https://registry.npmjs.org/lodash.escape/-/lodash.escape-3.2.0.tgz",
@@ -3482,12 +3576,6 @@
       "integrity": "sha1-eeTriMNqgSKvhvhEqpvNhRtfu1U=",
       "dev": true
     },
-    "lodash.isobject": {
-      "version": "3.0.2",
-      "resolved": "https://registry.npmjs.org/lodash.isobject/-/lodash.isobject-3.0.2.tgz",
-      "integrity": "sha1-PI+41bW/S/kK4G4U8qUwpO2TXh0=",
-      "dev": true
-    },
     "lodash.keys": {
       "version": "3.1.2",
       "resolved": "https://registry.npmjs.org/lodash.keys/-/lodash.keys-3.1.2.tgz",
@@ -3505,12 +3593,6 @@
       "integrity": "sha1-LcvSwofLwKVcxCMovQxzYVDVPj8=",
       "dev": true
     },
-    "lodash.merge": {
-      "version": "4.6.1",
-      "resolved": "https://registry.npmjs.org/lodash.merge/-/lodash.merge-4.6.1.tgz",
-      "integrity": "sha512-AOYza4+Hf5z1/0Hztxpm2/xiPZgi/cjMqdnKTUWTBSKchJlxXXuUSxCCl8rJlf4g6yww/j6mA8nC8Hw/EZWxKQ==",
-      "dev": true
-    },
     "lodash.restparam": {
       "version": "3.6.1",
       "resolved": "https://registry.npmjs.org/lodash.restparam/-/lodash.restparam-3.6.1.tgz",
@@ -4069,6 +4151,12 @@
       "integrity": "sha1-u+Z0BseaqFxc/sdm/lc0VV36EnQ=",
       "dev": true
     },
+    "p-map": {
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/p-map/-/p-map-1.2.0.tgz",
+      "integrity": "sha512-r6zKACMNhjPJMTl8KcFH4li//gkrXWfbD6feV8l6doRHlzljFWGJ2AP6iKaCJXyZmAUMOPtvbW7EXkbWO/pLEA==",
+      "dev": true
+    },
     "pako": {
       "version": "0.2.9",
       "resolved": "https://registry.npmjs.org/pako/-/pako-0.2.9.tgz",
@@ -4117,6 +4205,12 @@
         "path-root": "^0.1.1"
       }
     },
+    "parse-node-version": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/parse-node-version/-/parse-node-version-1.0.1.tgz",
+      "integrity": "sha512-3YHlOa/JgH6Mnpr05jP9eDG254US9ek25LyIxZlDItp2iJtwyaXQb57lBYLdT3MowkUFYEV2XXNAYIPlESvJlA==",
+      "dev": true
+    },
     "parse-passwd": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/parse-passwd/-/parse-passwd-1.0.0.tgz",
@@ -4222,6 +4316,12 @@
         "which": "^1.2.10"
       }
     },
+    "pify": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/pify/-/pify-3.0.0.tgz",
+      "integrity": "sha1-5aSs0sEB/fPZpNB/DbxNtJ3SgXY=",
+      "dev": true
+    },
     "pinkie": {
       "version": "2.0.4",
       "resolved": "https://registry.npmjs.org/pinkie/-/pinkie-2.0.4.tgz",
@@ -4238,34 +4338,15 @@
       }
     },
     "plugin-error": {
-      "version": "0.1.2",
-      "resolved": "https://registry.npmjs.org/plugin-error/-/plugin-error-0.1.2.tgz",
-      "integrity": "sha1-O5uzM1zPAPQl4HQ34ZJ2ln2kes4=",
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/plugin-error/-/plugin-error-1.0.1.tgz",
+      "integrity": "sha512-L1zP0dk7vGweZME2i+EeakvUNqSrdiI3F91TwEoYiGrAfUXmVv6fJIq4g82PAXxNsWOp0J7ZqQy/3Szz0ajTxA==",
       "dev": true,
       "requires": {
-        "ansi-cyan": "^0.1.1",
-        "ansi-red": "^0.1.1",
-        "arr-diff": "^1.0.1",
-        "arr-union": "^2.0.1",
-        "extend-shallow": "^1.1.2"
-      },
-      "dependencies": {
-        "arr-diff": {
-          "version": "1.1.0",
-          "resolved": "https://registry.npmjs.org/arr-diff/-/arr-diff-1.1.0.tgz",
-          "integrity": "sha1-aHwydYFjWI/vfeezb6vklesaOZo=",
-          "dev": true,
-          "requires": {
-            "arr-flatten": "^1.0.1",
-            "array-slice": "^0.2.3"
-          }
-        },
-        "array-slice": {
-          "version": "0.2.3",
-          "resolved": "https://registry.npmjs.org/array-slice/-/array-slice-0.2.3.tgz",
-          "integrity": "sha1-3Tz7gO15c6dRF82sabC5nshhhvU=",
-          "dev": true
-        }
+        "ansi-colors": "^1.0.1",
+        "arr-diff": "^4.0.0",
+        "arr-union": "^3.1.0",
+        "extend-shallow": "^3.0.2"
       }
     },
     "posix-character-classes": {
@@ -4396,27 +4477,6 @@
         "safe-buffer": "^5.1.0"
       }
     },
-    "rcfinder": {
-      "version": "0.1.9",
-      "resolved": "https://registry.npmjs.org/rcfinder/-/rcfinder-0.1.9.tgz",
-      "integrity": "sha1-8+gPOH3fmugK4wpBADKWQuroERU=",
-      "dev": true,
-      "requires": {
-        "lodash.clonedeep": "^4.3.2"
-      }
-    },
-    "rcloader": {
-      "version": "0.2.2",
-      "resolved": "https://registry.npmjs.org/rcloader/-/rcloader-0.2.2.tgz",
-      "integrity": "sha1-WNIpi0YtC5v9ITPSoex0+9cFxxc=",
-      "dev": true,
-      "requires": {
-        "lodash.assign": "^4.2.0",
-        "lodash.isobject": "^3.0.2",
-        "lodash.merge": "^4.6.0",
-        "rcfinder": "^0.1.6"
-      }
-    },
     "read-only-stream": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/read-only-stream/-/read-only-stream-2.0.0.tgz",
@@ -4656,6 +4716,81 @@
         "is-promise": "^2.1.0"
       }
     },
+    "run-sequence": {
+      "version": "2.2.1",
+      "resolved": "https://registry.npmjs.org/run-sequence/-/run-sequence-2.2.1.tgz",
+      "integrity": "sha512-qkzZnQWMZjcKbh3CNly2srtrkaO/2H/SI5f2eliMCapdRD3UhMrwjfOAZJAnZ2H8Ju4aBzFZkBGXUqFs9V0yxw==",
+      "dev": true,
+      "requires": {
+        "chalk": "^1.1.3",
+        "fancy-log": "^1.3.2",
+        "plugin-error": "^0.1.2"
+      },
+      "dependencies": {
+        "arr-diff": {
+          "version": "1.1.0",
+          "resolved": "https://registry.npmjs.org/arr-diff/-/arr-diff-1.1.0.tgz",
+          "integrity": "sha1-aHwydYFjWI/vfeezb6vklesaOZo=",
+          "dev": true,
+          "requires": {
+            "arr-flatten": "^1.0.1",
+            "array-slice": "^0.2.3"
+          }
+        },
+        "arr-union": {
+          "version": "2.1.0",
+          "resolved": "https://registry.npmjs.org/arr-union/-/arr-union-2.1.0.tgz",
+          "integrity": "sha1-IPnqtexw9cfSFbEHexw5Fh0pLH0=",
+          "dev": true
+        },
+        "array-slice": {
+          "version": "0.2.3",
+          "resolved": "https://registry.npmjs.org/array-slice/-/array-slice-0.2.3.tgz",
+          "integrity": "sha1-3Tz7gO15c6dRF82sabC5nshhhvU=",
+          "dev": true
+        },
+        "extend-shallow": {
+          "version": "1.1.4",
+          "resolved": "https://registry.npmjs.org/extend-shallow/-/extend-shallow-1.1.4.tgz",
+          "integrity": "sha1-Gda/lN/AnXa6cR85uHLSH/TdkHE=",
+          "dev": true,
+          "requires": {
+            "kind-of": "^1.1.0"
+          }
+        },
+        "fancy-log": {
+          "version": "1.3.3",
+          "resolved": "https://registry.npmjs.org/fancy-log/-/fancy-log-1.3.3.tgz",
+          "integrity": "sha512-k9oEhlyc0FrVh25qYuSELjr8oxsCoc4/LEZfg2iJJrfEk/tZL9bCoJE47gqAvI2m/AUjluCS4+3I0eTx8n3AEw==",
+          "dev": true,
+          "requires": {
+            "ansi-gray": "^0.1.1",
+            "color-support": "^1.1.3",
+            "parse-node-version": "^1.0.0",
+            "time-stamp": "^1.0.0"
+          }
+        },
+        "kind-of": {
+          "version": "1.1.0",
+          "resolved": "https://registry.npmjs.org/kind-of/-/kind-of-1.1.0.tgz",
+          "integrity": "sha1-FAo9LUGjbS78+pN3tiwk+ElaXEQ=",
+          "dev": true
+        },
+        "plugin-error": {
+          "version": "0.1.2",
+          "resolved": "https://registry.npmjs.org/plugin-error/-/plugin-error-0.1.2.tgz",
+          "integrity": "sha1-O5uzM1zPAPQl4HQ34ZJ2ln2kes4=",
+          "dev": true,
+          "requires": {
+            "ansi-cyan": "^0.1.1",
+            "ansi-red": "^0.1.1",
+            "arr-diff": "^1.0.1",
+            "arr-union": "^2.0.1",
+            "extend-shallow": "^1.1.2"
+          }
+        }
+      }
+    },
     "rxjs": {
       "version": "6.4.0",
       "resolved": "https://registry.npmjs.org/rxjs/-/rxjs-6.4.0.tgz",
diff --git a/package.json b/package.json
index c88ceba..f375a0e 100644
--- a/package.json
+++ b/package.json
@@ -8,13 +8,16 @@
   },
   "devDependencies": {
     "browserify": "^13.1.1",
+    "del": "^3.0.0",
     "eslint": "^5.14.1",
     "gulp": "^3.9.0",
-    "gulp-jshint": "^2.0.4",
+    "gulp-eslint": "^5.0.0",
     "gulp-qunit": "^1.5.0",
     "gulp-rename": "^1.2.2",
     "jshint": "^2.9.5",
+    "mkdirp": "^0.5.1",
     "qunit": "^1.0.0",
+    "run-sequence": "^2.2.1",
     "vinyl-buffer": "^1.0.0",
     "vinyl-source-stream": "^1.1.0"
   },
diff --git a/src/DragHandle.js b/src/DragHandle.js
index 34a8c4e..2b70243 100644
--- a/src/DragHandle.js
+++ b/src/DragHandle.js
@@ -8,7 +8,6 @@ var DragHandle = function (handler) {
   var _currentAxis;
   var _dragHandle;
   var _clickHandle = false;
-  var _movedHandle;
 
   // Event declarations
   var events = {
@@ -32,7 +31,6 @@ var DragHandle = function (handler) {
       }
 
       _dragHandle = false;
-      _movedHandle = false;
       _currentAxis = null;
       util.MouseMetrics.deletePreviousMouseData();
       handler.canvas.getImage().trigger('mouseup');
@@ -54,7 +52,6 @@ var DragHandle = function (handler) {
         y: 'movementY' in e.e ? e.e.movementY : (previousMouseData.y ? pageY - previousMouseData.y : 0)
       };
       util.MouseMetrics.setPreviousMouseData({x: pageX, y: pageY});
-      _movedHandle = true;
 
       if (_currentAxis === 'x') {
         handler.canvas.getImage().left -= movement.x;
diff --git a/src/MirrorHandler.js b/src/MirrorHandler.js
index 6a4c3c9..f0c08bc 100644
--- a/src/MirrorHandler.js
+++ b/src/MirrorHandler.js
@@ -9,7 +9,8 @@ function MirrorHandler(img) {
      * @return {MirrorHandler}
      */
   this.set = function(checked) {
-    _mirrored = (img.flipX = checked) ? 1 : 0;
+    img.flipX = checked;
+    _mirrored = checked ? 1 : 0;
     img.setCoords().canvas.renderAll();
 
     return this;
diff --git a/src/TextButton.js b/src/TextButton.js
index af5e53e..da41d41 100644
--- a/src/TextButton.js
+++ b/src/TextButton.js
@@ -15,7 +15,7 @@ function TextButton(id, text, settings, isActive) {
 
   fabric.Group.call(this);
 
-  var __active = isActive || false;
+  this.__active = isActive || false;
   var _callback = null;
   var _rect = null;
   var _text = null;
diff --git a/test/unit/image-editor.js b/test/unit/image-editor.js
index ef9c170..94024d3 100644
--- a/test/unit/image-editor.js
+++ b/test/unit/image-editor.js
@@ -1,3 +1,5 @@
+'use strict';
+
 (function() {
 
   QUnit.module('ImageEditor');