diff --git a/_config.php b/_config.php
index 98aeebc0..f743e824 100644
--- a/_config.php
+++ b/_config.php
@@ -17,14 +17,10 @@ use SilverStripe\View\Parsers\ShortcodeParser;
  * - CMS_PATH: Absolute filepath, e.g. "/var/www/my-webroot/cms"
  */
 call_user_func(function () {
-    define('CMS_PATH', __DIR__);
-
     // Check if CMS is root dir, or subdir
     if (strcasecmp(__DIR__, BASE_PATH) === 0) {
-        define('CMS_DIR', '');
         $clientPath = 'client';
     } else {
-        define('CMS_DIR', basename(__DIR__));
         $clientPath = basename(__DIR__) . '/client';
     }
 
diff --git a/code/Controllers/CMSMain.php b/code/Controllers/CMSMain.php
index 9a965a2d..3ce306fc 100644
--- a/code/Controllers/CMSMain.php
+++ b/code/Controllers/CMSMain.php
@@ -26,6 +26,7 @@ use SilverStripe\Control\HTTPResponse;
 use SilverStripe\Control\HTTPResponse_Exception;
 use SilverStripe\Core\Convert;
 use SilverStripe\Core\Injector\Injector;
+use SilverStripe\Core\Manifest\ModuleLoader;
 use Psr\SimpleCache\CacheInterface;
 use SilverStripe\Forms\DateField;
 use SilverStripe\Forms\DropdownField;
@@ -164,11 +165,13 @@ class CMSMain extends LeftAndMain implements CurrentPageIdentifier, PermissionPr
 
         parent::init();
 
-        Requirements::javascript(CMS_DIR . '/client/dist/js/bundle.js');
-        Requirements::javascript(CMS_DIR . '/client/dist/js/SilverStripeNavigator.js');
-        Requirements::css(CMS_DIR . '/client/dist/styles/bundle.css');
+        Requirements::javascript('silverstripe/cms: client/dist/js/bundle.js');
+        Requirements::javascript('silverstripe/cms: client/dist/js/SilverStripeNavigator.js');
+        Requirements::css('silverstripe/cms: client/dist/styles/bundle.css');
         Requirements::customCSS($this->generatePageIconsCss());
-        Requirements::add_i18n_javascript(CMS_DIR . '/client/lang', false, true);
+
+        $module = ModuleLoader::getModule('silverstripe/cms');
+        Requirements::add_i18n_javascript($module->getRelativeResourcePath('client/lang'), false, true);
 
         CMSBatchActionHandler::register('restore', CMSBatchAction_Restore::class);
         CMSBatchActionHandler::register('archive', CMSBatchAction_Archive::class);
diff --git a/code/Controllers/ContentController.php b/code/Controllers/ContentController.php
index a74997e4..6ee2e769 100644
--- a/code/Controllers/ContentController.php
+++ b/code/Controllers/ContentController.php
@@ -328,9 +328,9 @@ class ContentController extends Controller
 
         if (Director::isDev() || Permission::check('CMS_ACCESS_CMSMain') || Permission::check('VIEW_DRAFT_CONTENT')) {
             if ($this->dataRecord) {
-                Requirements::css(CMS_DIR . '/client/dist/styles/SilverStripeNavigator.css');
-                Requirements::javascript(ADMIN_THIRDPARTY_DIR . '/jquery/jquery.js');
-                Requirements::javascript(CMS_DIR . '/client/dist/js/SilverStripeNavigator.js');
+                Requirements::css('silverstripe/cms: client/dist/styles/SilverStripeNavigator.css');
+                Requirements::javascript('silverstripe/admin: thirdparty/jquery/jquery.js');
+                Requirements::javascript('silverstripe/cms: client/dist/js/SilverStripeNavigator.js');
 
                 $return = $nav = SilverStripeNavigator::get_for_record($this->dataRecord);
                 $items = $return['items'];
@@ -370,7 +370,7 @@ HTML;
         // On live sites we should still see the archived message
         } else {
             if ($date = Versioned::current_archived_date()) {
-                Requirements::css(CMS_DIR . '/client/dist/styles/SilverStripeNavigator.css');
+                Requirements::css('silverstripe/cms: client/dist/styles/SilverStripeNavigator.css');
                 /** @var DBDatetime $dateObj */
                 $dateObj = DBField::create_field('Datetime', $date);
                 // $dateObj->setVal($date);