diff --git a/composer.json b/composer.json
index 7d1e7a5..fd2d694 100644
--- a/composer.json
+++ b/composer.json
@@ -30,7 +30,8 @@
         "drupal/ui_patterns": "^1.0@RC",
         "drupal/viewsreference": "^1.2",
         "drupal/allowed_formats": "^1.1",
-        "drupal/textarea_widget_for_text": "^1.1"
+        "drupal/textarea_widget_for_text": "^1.1",
+        "drupal/customerror": "1.x-dev"
     },
     "repositories": {
         "drupal": {