diff --git a/.config/guix/system/default.scm b/.config/guix/system/default.scm
index 809b33f4..544ade3a 100644
--- a/.config/guix/system/default.scm
+++ b/.config/guix/system/default.scm
@@ -1,3 +1,5 @@
+;; To collect the size of a system:
+;; guix size $(guix system build config.scm)
 (define-module (default)
   #:use-module (gnu)
   #:use-module (gnu system nss)
diff --git a/.config/guix/system/desktop-fafafa.scm b/.config/guix/system/desktop-fafafa.scm
index f56e42b4..59459427 100644
--- a/.config/guix/system/desktop-fafafa.scm
+++ b/.config/guix/system/desktop-fafafa.scm
@@ -81,7 +81,7 @@
                  (name "francoise")
                  (group "users")
                  (supplementary-groups '("netdev" ; netdev is needed for networking.
-                                         "kvm"            ; For QEMU (and maybe libvirt)
+                                         "kvm"    ; For QEMU (and maybe libvirt)
                                          "video"))
                  (home-directory "/home/francoise"))
                 (operating-system-users default-operating-system)))