diff --git a/core/lib/Drupal.php b/core/lib/Drupal.php
index 1acfc12e9a6bb277f812312e0cbb02967cec36dc..b2c68aa2f46dfe1135f3b426accd6a730bcae5a3 100644
--- a/core/lib/Drupal.php
+++ b/core/lib/Drupal.php
@@ -81,7 +81,7 @@ class Drupal {
   /**
    * The current system version.
    */
-  const VERSION = '8.4.0-dev';
+  const VERSION = '8.4.0-alpha1';
 
   /**
    * Core API compatibility.