diff --git a/Gruntfile.js b/Gruntfile.js
index 5c37407d14..fbe4aa4c49 100644
--- a/Gruntfile.js
+++ b/Gruntfile.js
@@ -34,8 +34,6 @@ const path = require('path');
 
 module.exports = grunt => {
 
-    let clientLibList = [];
-
     let jsFilesToMinify = [
         'node_modules/jquery/dist/jquery.js',
         'node_modules/underscore/underscore.js',
diff --git a/application/Espo/Resources/metadata/app/jsLibs.json b/application/Espo/Resources/metadata/app/jsLibs.json
index 1b18696024..5ab38dea7f 100644
--- a/application/Espo/Resources/metadata/app/jsLibs.json
+++ b/application/Espo/Resources/metadata/app/jsLibs.json
@@ -24,7 +24,8 @@
         "exportsAs": "select2"
     },
     "Selectize": {
-        "path": "client/lib/selectize.min.js",
+        "path": "client/lib/selectize.js",
+        "devPath": "node_modules/selectize/dist/js/standalone/selectize.js",
         "exportsTo": "window",
         "exportsAs": "Selectize"
     },
diff --git a/client/src/app.js b/client/src/app.js
index 3be8b8d55b..5261806f9f 100644
--- a/client/src/app.js
+++ b/client/src/app.js
@@ -220,6 +220,7 @@ define(
                 this.language.loadDefault()
             ])
             .then(() => {
+                this.loader.isDeveloperMode = this.settings.get('isDeveloperMode');
                 this.loader.addLibsConfig(this.settings.get('jsLibs') || {});
 
                 this.user = new User();
diff --git a/client/src/loader.js b/client/src/loader.js
index 1f20781145..274e70f03e 100644
--- a/client/src/loader.js
+++ b/client/src/loader.js
@@ -43,6 +43,8 @@ var Espo = Espo || {classMap: {}};
         this._dataLoaded = {};
         this._loadingSubject = null;
         this._responseCache = null;
+
+        this.isDeveloperMode = false;
     };
 
     _.extend(Espo.Loader.prototype, {
@@ -255,6 +257,10 @@ var Espo = Espo || {classMap: {}};
 
                     path = libData.path || path;
 
+                    if (this.isDeveloperMode) {
+                        path = libData.devPath || path;
+                    }
+
                     exportsTo = libData.exportsTo || exportsTo;
                     exportsAs = libData.exportsAs || exportsAs;
                 }
diff --git a/html/main.html b/html/main.html
index fe2d838ab0..9862b3c3f0 100644
--- a/html/main.html
+++ b/html/main.html
@@ -16,17 +16,18 @@
         <link rel="icon" href="{{basePath}}{{faviconPath}}" type="image/x-icon">
         <link rel="shortcut icon" href="{{basePath}}{{faviconPath}}" type="image/x-icon">
         <script type="text/javascript">
-            $(function () {
+            $(() => {
                 Espo.loader.cacheTimestamp = {{loaderCacheTimestamp}};
-                Espo.require('{{appClientClassName}}', function (App) {
-                    var app = new App({
+
+                require('{{appClientClassName}}', App => {
+                    new App({
                         id: '{{applicationId}}',
                         useCache: {{useCache}},
                         cacheTimestamp: {{cacheTimestamp}},
                         basePath: '{{basePath}}',
                         apiUrl: '{{apiUrl}}',
                         ajaxTimeout: {{ajaxTimeout}},
-                    }, function (app) {
+                    }, app => {
                         {{runScript}}
                     });
                 });
diff --git a/package-lock.json b/package-lock.json
index a051f7a267..2cef092772 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -30,6 +30,11 @@
         "color-convert": "^1.9.0"
       }
     },
+    "ansicolors": {
+      "version": "0.2.1",
+      "resolved": "https://registry.npmjs.org/ansicolors/-/ansicolors-0.2.1.tgz",
+      "integrity": "sha1-vgiVmQl7dKXJxKhKDNvNtivYeu8="
+    },
     "applause": {
       "version": "1.2.2",
       "resolved": "https://registry.npmjs.org/applause/-/applause-1.2.2.tgz",
@@ -458,6 +463,15 @@
         "map-obj": "^1.0.0"
       }
     },
+    "cardinal": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/cardinal/-/cardinal-1.0.0.tgz",
+      "integrity": "sha1-UOIcGwqjdyn5N33vGWtanOyTLuk=",
+      "requires": {
+        "ansicolors": "~0.2.1",
+        "redeyed": "~1.0.0"
+      }
+    },
     "chalk": {
       "version": "2.4.2",
       "resolved": "https://registry.npmjs.org/chalk/-/chalk-2.4.2.tgz",
@@ -641,6 +655,11 @@
         }
       }
     },
+    "csv-parse": {
+      "version": "4.16.0",
+      "resolved": "https://registry.npmjs.org/csv-parse/-/csv-parse-4.16.0.tgz",
+      "integrity": "sha512-Zb4tGPANH4SW0LgC9+s9Mnequs9aqn7N3/pCqNbVjs2XhEF6yWNU2Vm4OGl1v2Go9nw8rXt87Cm2QN/o6Vpqgg=="
+    },
     "currently-unhandled": {
       "version": "0.4.1",
       "resolved": "https://registry.npmjs.org/currently-unhandled/-/currently-unhandled-0.4.1.tgz",
@@ -1721,6 +1740,11 @@
       "integrity": "sha512-mxIDAb9Lsm6DoOJ7xH+5+X4y1LU/4Hi50L9C5sIswK3JzULS4bwk1FvjdBgvYR4bzT4tuUQiC15FE2f5HbLvYw==",
       "dev": true
     },
+    "humanize": {
+      "version": "0.0.9",
+      "resolved": "https://registry.npmjs.org/humanize/-/humanize-0.0.9.tgz",
+      "integrity": "sha1-GZT/rs3+nEQe0r2sdFK3u0yeQaQ="
+    },
     "iconv-lite": {
       "version": "0.4.24",
       "resolved": "https://registry.npmjs.org/iconv-lite/-/iconv-lite-0.4.24.tgz",
@@ -1984,6 +2008,12 @@
       "resolved": "https://registry.npmjs.org/jquery-textcomplete/-/jquery-textcomplete-1.8.5.tgz",
       "integrity": "sha512-WctSUxFk7GF5Tx2gHeVKrpkQ9tsV7mibBJ0AYNwEx+Zx3ZoUQgU5grkBXY3SCqpq/owMAMEvksN96DBSWT4PSg=="
     },
+    "jquery-ui": {
+      "version": "1.12.1",
+      "resolved": "https://registry.npmjs.org/jquery-ui/-/jquery-ui-1.12.1.tgz",
+      "integrity": "sha1-vLQEXI3QU5wTS8FIjN0+dop6nlE=",
+      "optional": true
+    },
     "js-yaml": {
       "version": "3.13.1",
       "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.13.1.tgz",
@@ -2079,8 +2109,7 @@
     "lodash": {
       "version": "4.17.21",
       "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.21.tgz",
-      "integrity": "sha512-v2kDEe57lecTulaDIuNTPy3Ry4gLGJ6Z1O3vE1krgXZNrsQ+LFTGHVxVjcXPs17LhbZVGedAJv8XZ1tvj5FvSg==",
-      "dev": true
+      "integrity": "sha512-v2kDEe57lecTulaDIuNTPy3Ry4gLGJ6Z1O3vE1krgXZNrsQ+LFTGHVxVjcXPs17LhbZVGedAJv8XZ1tvj5FvSg=="
     },
     "lodash.defaults": {
       "version": "4.2.0",
@@ -2254,6 +2283,11 @@
         "to-regex": "^3.0.2"
       }
     },
+    "microplugin": {
+      "version": "0.0.3",
+      "resolved": "https://registry.npmjs.org/microplugin/-/microplugin-0.0.3.tgz",
+      "integrity": "sha1-H8Lhu3yeGegr2Eu6kTe75xJQ2M0="
+    },
     "mime": {
       "version": "1.6.0",
       "resolved": "https://registry.npmjs.org/mime/-/mime-1.6.0.tgz",
@@ -2493,6 +2527,27 @@
         "wrappy": "1"
       }
     },
+    "optimist": {
+      "version": "0.6.1",
+      "resolved": "https://registry.npmjs.org/optimist/-/optimist-0.6.1.tgz",
+      "integrity": "sha1-2j6nRob6IaGaERwybpDrFaAZZoY=",
+      "requires": {
+        "minimist": "~0.0.1",
+        "wordwrap": "~0.0.2"
+      },
+      "dependencies": {
+        "minimist": {
+          "version": "0.0.10",
+          "resolved": "https://registry.npmjs.org/minimist/-/minimist-0.0.10.tgz",
+          "integrity": "sha1-3j+YVD2/lggr5IrRoMfNqDYwHc8="
+        },
+        "wordwrap": {
+          "version": "0.0.3",
+          "resolved": "https://registry.npmjs.org/wordwrap/-/wordwrap-0.0.3.tgz",
+          "integrity": "sha1-o9XabNXAvAAI03I0u68b7WMFkQc="
+        }
+      }
+    },
     "os-homedir": {
       "version": "1.0.2",
       "resolved": "https://registry.npmjs.org/os-homedir/-/os-homedir-1.0.2.tgz",
@@ -2719,6 +2774,21 @@
         "strip-indent": "^1.0.1"
       }
     },
+    "redeyed": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/redeyed/-/redeyed-1.0.1.tgz",
+      "integrity": "sha1-6WwZO0DAgWsArshCaY5hGF5VSYo=",
+      "requires": {
+        "esprima": "~3.0.0"
+      },
+      "dependencies": {
+        "esprima": {
+          "version": "3.0.0",
+          "resolved": "https://registry.npmjs.org/esprima/-/esprima-3.0.0.tgz",
+          "integrity": "sha1-U88kes2ncxPlUcOqLnM0LT+099k="
+        }
+      }
+    },
     "regex-not": {
       "version": "1.0.2",
       "resolved": "https://registry.npmjs.org/regex-not/-/regex-not-1.0.2.tgz",
@@ -2828,6 +2898,15 @@
       "integrity": "sha512-YZo3K82SD7Riyi0E1EQPojLz7kpepnSQI9IyPbHHg1XXXevb5dJI7tpyN2ADxGcQbHG7vcyRHk0cbwqcQriUtg==",
       "dev": true
     },
+    "selectize": {
+      "version": "git://github.com/selectize/selectize.js.git#18ae944e92bce8576a1864503200114779569a18",
+      "from": "git://github.com/selectize/selectize.js.git#v0.13.3",
+      "requires": {
+        "jquery-ui": "^1.12.1",
+        "microplugin": "0.0.3",
+        "sifter": "^0.5.4"
+      }
+    },
     "semver": {
       "version": "5.7.1",
       "resolved": "https://registry.npmjs.org/semver/-/semver-5.7.1.tgz",
@@ -2863,6 +2942,28 @@
       "integrity": "sha1-xUmCuZbHbvDB5rWfvcWCX1txMRM=",
       "dev": true
     },
+    "sifter": {
+      "version": "0.5.4",
+      "resolved": "https://registry.npmjs.org/sifter/-/sifter-0.5.4.tgz",
+      "integrity": "sha512-t2yxTi/MM/ESup7XH5oMu8PUcttlekt269RqxARgnvS+7D/oP6RyA1x3M/5w8dG9OgkOyQ8hNRWelQ8Rj4TAQQ==",
+      "requires": {
+        "async": "^2.6.0",
+        "cardinal": "^1.0.0",
+        "csv-parse": "^4.6.5",
+        "humanize": "^0.0.9",
+        "optimist": "^0.6.1"
+      },
+      "dependencies": {
+        "async": {
+          "version": "2.6.3",
+          "resolved": "https://registry.npmjs.org/async/-/async-2.6.3.tgz",
+          "integrity": "sha512-zflvls11DCy+dQWzTW2dzuilv8Z5X/pjfmZOWba6TNIVDm+2UDaJmXSOXlasHKfNBs8oo3M0aT50fDEWfKZjXg==",
+          "requires": {
+            "lodash": "^4.17.14"
+          }
+        }
+      }
+    },
     "signal-exit": {
       "version": "3.0.3",
       "resolved": "https://registry.npmjs.org/signal-exit/-/signal-exit-3.0.3.tgz",
diff --git a/package.json b/package.json
index 3dbc7eaf35..cf784e293d 100644
--- a/package.json
+++ b/package.json
@@ -49,6 +49,7 @@
     "marked": "^0.8.2",
     "moment": "^2.24.0",
     "moment-timezone": "^0.5.33",
+    "selectize": "git://github.com/selectize/selectize.js.git#v0.13.3",
     "timepicker": "^1.11.15",
     "underscore": "^1.13.1"
   }