diff --git a/composer.dev.json b/composer.dev.json
index edada0b..bcc2ab2 100644
--- a/composer.dev.json
+++ b/composer.dev.json
@@ -41,7 +41,8 @@
         "sort-packages": true
     },
     "conflict": {
-        "drupal/core": "7.*"
+        "drupal/core": "7.*",
+        "drupal/coder": ">8.3.8"
     },
     "repositories": {
         "drupal": {