diff --git a/nixos/modules/system/boot/systemd/tmpfiles.nix b/nixos/modules/system/boot/systemd/tmpfiles.nix
index 631a02645d9b..b43d91d58dd0 100644
--- a/nixos/modules/system/boot/systemd/tmpfiles.nix
+++ b/nixos/modules/system/boot/systemd/tmpfiles.nix
@@ -25,6 +25,8 @@ let
     " "
     "\\"
   ];
+  hasTmpfilesPrefix = lib.hasPrefix "tmpfiles.d/";
+  removeTmpFilesPrefix = lib.removePrefix "tmpfiles.d/";
 
   settingsOption = {
     description = ''
@@ -299,8 +301,8 @@ in
           ''
           + concatMapStrings (
             name:
-            optionalString (hasPrefix "tmpfiles.d/" name) ''
-              rm -f $out/${removePrefix "tmpfiles.d/" name}
+            optionalString (hasTmpfilesPrefix name) ''
+              rm -f $out/${removeTmpFilesPrefix name}
             ''
           ) config.system.build.etc.passthru.targets;
         })