diff --git a/composer.json b/composer.json
index 76ba1b2cbc..3ba23e4ec9 100644
--- a/composer.json
+++ b/composer.json
@@ -25,6 +25,6 @@
   "require": {
     "php": ">=7.0.0",
     "johnpbloch/wordpress-core-installer": "^1.0 || ^2.0",
-    "johnpbloch/wordpress-core": "dev-master"
+    "johnpbloch/wordpress-core": "6.3.5"
   }
 }