diff --git a/fluent.runtime/fluent/runtime/builtins.py b/fluent.runtime/fluent/runtime/builtins.py
index cb16f9d8..02e817b8 100644
--- a/fluent.runtime/fluent/runtime/builtins.py
+++ b/fluent.runtime/fluent/runtime/builtins.py
@@ -1,4 +1,4 @@
-from typing import Any, Callable, Dict
+from typing import Callable, Dict
 
 from .types import FluentType, fluent_date, fluent_number
 
@@ -6,7 +6,7 @@
 DATETIME = fluent_date
 
 
-BUILTINS: Dict[str, Callable[[Any], FluentType]] = {
+BUILTINS: Dict[str, Callable[..., FluentType]] = {
     "NUMBER": NUMBER,
     "DATETIME": DATETIME,
 }
diff --git a/fluent.runtime/fluent/runtime/bundle.py b/fluent.runtime/fluent/runtime/bundle.py
index 6a0f254d..a88fdab7 100644
--- a/fluent.runtime/fluent/runtime/bundle.py
+++ b/fluent.runtime/fluent/runtime/bundle.py
@@ -35,7 +35,7 @@ class FluentBundle:
     def __init__(
         self,
         locales: List[str],
-        functions: Union[Dict[str, Callable[[Any], "FluentType"]], None] = None,
+        functions: Union[Dict[str, Callable[..., "FluentType"]], None] = None,
         use_isolating: bool = True,
     ):
         self.locales = locales