diff --git a/modules/installer/grub/grub-menu-builder.sh b/modules/installer/grub/grub-menu-builder.sh
index 0605df5f52c5..4caafe9da63b 100644
--- a/modules/installer/grub/grub-menu-builder.sh
+++ b/modules/installer/grub/grub-menu-builder.sh
@@ -250,8 +250,8 @@ for link in $((ls -d $defaultConfig/fine-tune/* ) | sort -n); do
 done
 
 for generation in $(
-    (cd /nix/var/nix/profiles && echo system-*-link) \
-    | sed 's/system-\([0-9]\+\)-link/\1/g' \
+    (cd /nix/var/nix/profiles && for i in system-*-link; do echo $i; done) \
+    | sed 's/system-\([0-9]\+\)-link/\1/' \
     | sort -n -r); do
     link=/nix/var/nix/profiles/system-$generation-link
     date=$(stat --printf="%y\n" $link | sed 's/\..*//')