diff --git a/pkgs/by-name/ni/nixos-rebuild-ng/src/nixos_rebuild/__init__.py b/pkgs/by-name/ni/nixos-rebuild-ng/src/nixos_rebuild/__init__.py
index 057be3017a63..49ba193a03ad 100644
--- a/pkgs/by-name/ni/nixos-rebuild-ng/src/nixos_rebuild/__init__.py
+++ b/pkgs/by-name/ni/nixos-rebuild-ng/src/nixos_rebuild/__init__.py
@@ -16,6 +16,12 @@ from .utils import Args, LogFormatter
 logger = logging.getLogger()
 logger.setLevel(logging.INFO)
 
+# Build-time flags
+# Strings to avoid breaking standalone (e.g.: `python -m nixos_rebuild`) usage
+EXECUTABLE = "@executable@"
+WITH_REEXEC = "@withReexec@"
+WITH_SHELL_FILES = "@withShellFiles@"
+
 
 def get_parser() -> tuple[argparse.ArgumentParser, dict[str, argparse.ArgumentParser]]:
     common_flags = argparse.ArgumentParser(add_help=False)
@@ -181,8 +187,8 @@ def parse_args(
     }
 
     if args.help or args.action is None:
-        if "@withShellFiles@" == "true":  # type: ignore
-            r = run(["man", "8", "@executable@"], check=False)
+        if WITH_SHELL_FILES == "true":
+            r = run(["man", "8", EXECUTABLE], check=False)
             parser.exit(r.returncode)
         else:
             parser.print_help()
@@ -260,10 +266,9 @@ def reexec(
         logger.warning("could not find a newer version of nixos-rebuild")
 
     if drv:
-        new = drv / "bin/@executable@"
+        new = drv / f"bin/{EXECUTABLE}"
         current = Path(argv[0])
-        # Disable re-exec during development
-        if current.name != "__main__.py" and new != current:
+        if new != current:
             logging.debug(
                 "detected newer version of script, re-exec'ing, current=%s, new=%s",
                 argv[0],
@@ -298,7 +303,7 @@ def execute(argv: list[str]) -> None:
     # Re-exec to a newer version of the script before building to ensure we get
     # the latest fixes
     if (
-        "@withReexec@" == "true"  # type: ignore
+        WITH_REEXEC == "true"
         and can_run
         and not args.fast
         and not os.environ.get("_NIXOS_REBUILD_REEXEC")