diff --git a/pkgs/clan-cli/clan_lib/flake/flake.py b/pkgs/clan-cli/clan_lib/flake/flake.py
index b84cd07e4..4ed762e3e 100644
--- a/pkgs/clan-cli/clan_lib/flake/flake.py
+++ b/pkgs/clan-cli/clan_lib/flake/flake.py
@@ -731,7 +731,7 @@ class Flake:
             self.invalidate_cache()
         assert self._cache is not None
 
-        nix_options = self.nix_options if self.nix_options is not None else []
+        nix_options = self.nix_options[:] if self.nix_options is not None else []
 
         str_selectors: list[str] = []
         for selector in selectors: