diff --git a/guix/gexp.scm b/guix/gexp.scm
index 510a1d54c3..67b6121313 100644
--- a/guix/gexp.scm
+++ b/guix/gexp.scm
@@ -1443,6 +1443,7 @@ to the source files instead of copying them."
                       #:system system
                       #:guile-for-build guile
                       #:local-build? #t
+                      #:substitutable? #f
 
                       ;; Avoid deprecation warnings about the use of the _IO*
                       ;; constants in (guix build utils).