diff --git a/nixos/modules/system/boot/systemd/user.nix b/nixos/modules/system/boot/systemd/user.nix
index 4951aef9558..0b1e6277c2f 100644
--- a/nixos/modules/system/boot/systemd/user.nix
+++ b/nixos/modules/system/boot/systemd/user.nix
@@ -14,6 +14,7 @@ let
     generateUnits
     targetToUnit
     serviceToUnit
+    sliceToUnit
     socketToUnit
     timerToUnit
     pathToUnit;