diff --git a/gnu/system.scm b/gnu/system.scm
index c4404f593..528527ba9 100644
--- a/gnu/system.scm
+++ b/gnu/system.scm
@@ -278,6 +278,8 @@ directly by the user."
 
       (store-device
        (match (assq 'store rest)
+         (('store ('device #f) _ ...)
+          root-device)
          (('store ('device device) _ ...)
           (device-sexp->device device))
          (_                                       ;the old format
@@ -902,6 +904,7 @@ device in a <menu-entry>."
   (case (file-system-title fs)
     ((uuid) (file-system-device fs))
     ((label) (file-system-device fs))
+    ((device) (file-system-device fs))
     (else #f)))
 
 (define (operating-system-boot-parameters os system.drv root-device)