diff --git a/nixos/modules/system/boot/loader/systemd-boot/systemd-boot-builder.py b/nixos/modules/system/boot/loader/systemd-boot/systemd-boot-builder.py
index 694d34d1c059..9943b2e86f30 100644
--- a/nixos/modules/system/boot/loader/systemd-boot/systemd-boot-builder.py
+++ b/nixos/modules/system/boot/loader/systemd-boot/systemd-boot-builder.py
@@ -214,8 +214,8 @@ def get_generations(profile: str | None = None) -> list[SystemIdentifier]:
 
 
 def remove_old_entries(gens: list[SystemIdentifier]) -> None:
-    rex_profile = re.compile(r"^" + re.escape(BOOT_MOUNT_POINT) + "/loader/entries/nixos-(.*)-generation-.*\.conf$")
-    rex_generation = re.compile(r"^" + re.escape(BOOT_MOUNT_POINT) + "/loader/entries/nixos.*-generation-([0-9]+)(-specialisation-.*)?\.conf$")
+    rex_profile = re.compile(r"^" + re.escape(BOOT_MOUNT_POINT) + r"/loader/entries/nixos-(.*)-generation-.*\.conf$")
+    rex_generation = re.compile(r"^" + re.escape(BOOT_MOUNT_POINT) + r"/loader/entries/nixos.*-generation-([0-9]+)(-specialisation-.*)?\.conf$")
     known_paths = []
     for gen in gens:
         bootspec = get_bootspec(gen.profile, gen.generation)