diff --git a/modules/freya/system.scm b/modules/freya/system.scm
index 161fa3b..9d201ed 100644
--- a/modules/freya/system.scm
+++ b/modules/freya/system.scm
@@ -224,7 +224,16 @@
           ; openssh
           (service openssh-service-type))
     ;; append guix base services
-    %base-services))
+    (modify-services %base-services
+      (guix-service-type config =>
+        (guix-configuration
+          (inherit config)
+          (substitute-urls
+            (append (list "https://substitutes.nonguix.org")
+                    %default-substitute-urls))
+          (authorized-keys
+            (append (list (local-file "../../certs/non-guix.pub"))
+                    %default-authorized-guix-keys)))))))
 
 (define-public %desktop-freya-services
   (append