diff --git a/.config/guix/config.scm b/.config/guix/config.scm
index d2224bb6..a5780196 100644
--- a/.config/guix/config.scm
+++ b/.config/guix/config.scm
@@ -68,13 +68,18 @@
 (define %my-services
   (modify-services
       %desktop-services
-    ;; (guix-service-type config =>
-    ;;                    (guix-configuration
-    ;;                     (inherit config)
-    ;;                     ;; Don't clean build deps.
-    ;;                     ;; See (info "(guix) Invoking guix-daemon").
-    ;;                     ;; WARNING: This tends to yield an ever-growing store.
-    ;;                     (extra-options '("--gc-keep-outputs"))))
+    (guix-service-type config =>
+                       (guix-configuration
+                        (inherit config)
+                        ;; Don't clean build deps.
+                        ;; See (info "(guix) Invoking guix-daemon").
+                        ;; WARNING: This tends to yield an ever-growing store.
+                        ;; (extra-options '("--gc-keep-outputs"))
+                        (substitute-urls
+                         (list
+                          "https://berlin.guixsd.org"
+                          "https://mirror.hydra.gnu.org"
+                          "https://hydra.gnu.org"))))
     (udev-service-type config =>
                        (udev-configuration
                         (inherit config)