diff --git a/gulpfile.js b/gulpfile.js
index cd01a9d5f..b71ce0703 100644
--- a/gulpfile.js
+++ b/gulpfile.js
@@ -28,8 +28,14 @@ const uglify = require('gulp-uglify-es').default
 const babel = require('gulp-babel')
 const debug = require('gulp-debug')
 const pify = require('pify')
+const gulpMultiProcess = require('gulp-multi-process')
 const endOfStream = pify(require('end-of-stream'))
 
+function gulpParallel (...args) {
+  return function spawnGulpChildProcess(cb) {
+    return gulpMultiProcess(args, cb, true)
+  }
+}
 
 const browserPlatforms = [
   'firefox',
@@ -420,7 +426,7 @@ gulp.task('build',
   gulp.series(
     'clean',
     'build:scss',
-    gulp.parallel(
+    gulpParallel(
       'build:extension:js',
       'build:mascara:js',
       'copy'
@@ -478,6 +484,16 @@ function generateBundler(opts, performBundle) {
 
   let bundler = browserify(browserifyOpts)
 
+  // Minification
+  if (opts.minifyBuild) {
+    bundler.transform('uglifyify', {
+      global: true,
+      mangle: {
+        reserved: [ 'MetamaskInpageProvider' ]
+      },
+    })
+  }
+
   if (opts.watch) {
     bundler = watchify(bundler)
     // on any file update, re-runs the bundler
@@ -546,7 +562,6 @@ function bundleTask(opts) {
       // buffer file contents (?)
       .pipe(buffer())
 
-
     // Initialize Source Maps
     if (opts.buildSourceMaps) {
       buildStream = buildStream
@@ -554,16 +569,6 @@ function bundleTask(opts) {
         .pipe(sourcemaps.init({ loadMaps: true }))
     }
 
-    // Minification
-    if (opts.minifyBuild) {
-      buildStream = buildStream
-        .pipe(uglify({
-          mangle: {
-            reserved: [ 'MetamaskInpageProvider' ]
-          },
-        }))
-    }
-
     // Finalize Source Maps (writes .map file)
     if (opts.buildSourceMaps) {
       buildStream = buildStream
diff --git a/package-lock.json b/package-lock.json
index 8a2d642e0..1029c507f 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -919,6 +919,65 @@
         "async-done": "1.2.4"
       }
     },
+    "async.queue": {
+      "version": "0.5.2",
+      "resolved": "https://registry.npmjs.org/async.queue/-/async.queue-0.5.2.tgz",
+      "integrity": "sha1-jV2QgS4UgQZrwJBOjMFxKxfDvXw=",
+      "dev": true,
+      "requires": {
+        "async.util.queue": "0.5.2"
+      }
+    },
+    "async.util.arrayeach": {
+      "version": "0.5.2",
+      "resolved": "https://registry.npmjs.org/async.util.arrayeach/-/async.util.arrayeach-0.5.2.tgz",
+      "integrity": "sha1-WMTpgCjVXWm/sFrrOvROClVagpw=",
+      "dev": true
+    },
+    "async.util.isarray": {
+      "version": "0.5.2",
+      "resolved": "https://registry.npmjs.org/async.util.isarray/-/async.util.isarray-0.5.2.tgz",
+      "integrity": "sha1-5i2sjyY29lh13PdSHC0k0N+yu98=",
+      "dev": true
+    },
+    "async.util.map": {
+      "version": "0.5.2",
+      "resolved": "https://registry.npmjs.org/async.util.map/-/async.util.map-0.5.2.tgz",
+      "integrity": "sha1-5YjvhuCzq18CfZevTWg10FXKadY=",
+      "dev": true
+    },
+    "async.util.noop": {
+      "version": "0.5.2",
+      "resolved": "https://registry.npmjs.org/async.util.noop/-/async.util.noop-0.5.2.tgz",
+      "integrity": "sha1-vdYrl8sKo/YLWGrRSEaGmJdeWLk=",
+      "dev": true
+    },
+    "async.util.onlyonce": {
+      "version": "0.5.2",
+      "resolved": "https://registry.npmjs.org/async.util.onlyonce/-/async.util.onlyonce-0.5.2.tgz",
+      "integrity": "sha1-uOb8AErckjFk154y8oE+5GXCT/I=",
+      "dev": true
+    },
+    "async.util.queue": {
+      "version": "0.5.2",
+      "resolved": "https://registry.npmjs.org/async.util.queue/-/async.util.queue-0.5.2.tgz",
+      "integrity": "sha1-V/Zavho83yc9MavSirlUJfgiLuU=",
+      "dev": true,
+      "requires": {
+        "async.util.arrayeach": "0.5.2",
+        "async.util.isarray": "0.5.2",
+        "async.util.map": "0.5.2",
+        "async.util.noop": "0.5.2",
+        "async.util.onlyonce": "0.5.2",
+        "async.util.setimmediate": "0.5.2"
+      }
+    },
+    "async.util.setimmediate": {
+      "version": "0.5.2",
+      "resolved": "https://registry.npmjs.org/async.util.setimmediate/-/async.util.setimmediate-0.5.2.tgz",
+      "integrity": "sha1-KBLrq/KlgCd1jUvHeT0cz68QJV8=",
+      "dev": true
+    },
     "asynckit": {
       "version": "0.4.0",
       "resolved": "https://registry.npmjs.org/asynckit/-/asynckit-0.4.0.tgz",
@@ -9290,6 +9349,15 @@
         }
       }
     },
+    "gulp-multi-process": {
+      "version": "1.3.1",
+      "resolved": "https://registry.npmjs.org/gulp-multi-process/-/gulp-multi-process-1.3.1.tgz",
+      "integrity": "sha512-okxYy3mxUkekM0RNjkBg8OPuzpnD2yXMAdnGOaQPSJ2wzBdE9R9pkTV+tzPZ65ORK7b57YUc6s+gROA4+EIOLg==",
+      "dev": true,
+      "requires": {
+        "async.queue": "0.5.2"
+      }
+    },
     "gulp-replace": {
       "version": "0.6.1",
       "resolved": "https://registry.npmjs.org/gulp-replace/-/gulp-replace-0.6.1.tgz",
diff --git a/package.json b/package.json
index e8f83016c..fa91c69e4 100644
--- a/package.json
+++ b/package.json
@@ -229,6 +229,7 @@
     "gulp-eslint": "^4.0.0",
     "gulp-json-editor": "^2.2.1",
     "gulp-livereload": "^3.8.1",
+    "gulp-multi-process": "^1.3.1",
     "gulp-replace": "^0.6.1",
     "gulp-sourcemaps": "^2.6.0",
     "gulp-stylefmt": "^1.1.0",
@@ -272,7 +273,7 @@
     "stylelint-config-standard": "^18.2.0",
     "tape": "^4.5.1",
     "testem": "^2.0.0",
-    "uglifyify": "^4.0.2",
+    "uglifyify": "^4.0.5",
     "vinyl-buffer": "^1.0.1",
     "vinyl-source-stream": "^2.0.0",
     "watchify": "^3.9.0"