diff --git a/defaults/install/build.xml b/defaults/install/build.xml
index 7544d3d6..ff91ef1e 100644
--- a/defaults/install/build.xml
+++ b/defaults/install/build.xml
@@ -127,6 +127,9 @@
 
         <!-- Run Drupal Check. -->
         <foreach list="${drupal-check.directories}" param="drupal-check.dir" target="drupal-check" />
+
+        <!-- Ensure the composer.lock file is up to date -->
+        <exec command="composer validate --no-check-all --no-check-publish" logoutput="true" checkreturn="true" />
     </target>