diff --git a/pkgs/by-name/ni/nixos-rebuild-ng/src/nixos_rebuild/process.py b/pkgs/by-name/ni/nixos-rebuild-ng/src/nixos_rebuild/process.py
index f7c83f714937..54c8b71036e9 100644
--- a/pkgs/by-name/ni/nixos-rebuild-ng/src/nixos_rebuild/process.py
+++ b/pkgs/by-name/ni/nixos-rebuild-ng/src/nixos_rebuild/process.py
@@ -5,13 +5,13 @@ import shlex
 import subprocess
 from dataclasses import dataclass
 from getpass import getpass
-from typing import Self, Sequence, TypedDict, Unpack
+from typing import Final, Self, Sequence, TypedDict, Unpack
 
 from . import tmpdir
 
 logger = logging.getLogger(__name__)
 
-SSH_DEFAULT_OPTS = [
+SSH_DEFAULT_OPTS: Final = [
     "-o",
     "ControlMaster=auto",
     "-o",
diff --git a/pkgs/by-name/ni/nixos-rebuild-ng/src/nixos_rebuild/tmpdir.py b/pkgs/by-name/ni/nixos-rebuild-ng/src/nixos_rebuild/tmpdir.py
index ca71a6ddd8c3..521af84ce464 100644
--- a/pkgs/by-name/ni/nixos-rebuild-ng/src/nixos_rebuild/tmpdir.py
+++ b/pkgs/by-name/ni/nixos-rebuild-ng/src/nixos_rebuild/tmpdir.py
@@ -1,5 +1,6 @@
 from pathlib import Path
 from tempfile import TemporaryDirectory
+from typing import Final
 
-TMPDIR = TemporaryDirectory(prefix="nixos-rebuild.")
-TMPDIR_PATH = Path(TMPDIR.name)
+TMPDIR: Final = TemporaryDirectory(prefix="nixos-rebuild.")
+TMPDIR_PATH: Final = Path(TMPDIR.name)