diff --git a/src/timeout_executor/subprocess.py b/src/timeout_executor/subprocess.py
index 33e8d16..81010ea 100644
--- a/src/timeout_executor/subprocess.py
+++ b/src/timeout_executor/subprocess.py
@@ -2,12 +2,15 @@
 
 from __future__ import annotations
 
-from collections.abc import Awaitable
+from functools import partial
+from inspect import isawaitable
 from os import environ
 from pathlib import Path
 from typing import TYPE_CHECKING, Any, Callable
 
+import anyio
 import cloudpickle
+from anyio.lowlevel import checkpoint
 
 from timeout_executor.const import TIMEOUT_EXECUTOR_INPUT_FILE
 
@@ -39,11 +42,12 @@ def dumps_value(value: Any) -> bytes:
 
 def output_to_file(file: str) -> Callable[[Callable[P, T]], Callable[P, T]]:
     def wrapper(func: Callable[P, T]) -> Callable[P, T]:
+        func = wrap_function_as_sync(func)
+
         def inner(*args: P.args, **kwargs: P.kwargs) -> T:
             dump = b""
             try:
                 result = func(*args, **kwargs)
-                result = wrap_awaitable(result)
             except BaseException as exc:
                 dump = dumps_value(exc)
                 raise
@@ -59,10 +63,22 @@ def inner(*args: P.args, **kwargs: P.kwargs) -> T:
     return wrapper
 
 
-def wrap_awaitable(value: Any) -> Any:
-    if not isinstance(value, Awaitable):
-        return value
+def wrap_function_as_async(func: Callable[P, Any]) -> Callable[P, Any]:
+    async def wrapped(*args: P.args, **kwargs: P.kwargs) -> Any:
+        await checkpoint()
+        result = func(*args, **kwargs)
+        if isawaitable(result):
+            return await result
+        return result
+
+    return wrapped
+
+
+def wrap_function_as_sync(func: Callable[P, Any]) -> Callable[P, Any]:
+    async_wrapped = wrap_function_as_async(func)
 
-    from async_wrapper import async_to_sync
+    def wrapped(*args: P.args, **kwargs: P.kwargs) -> Any:
+        new_func = partial(async_wrapped, *args, **kwargs)
+        return anyio.run(new_func)
 
-    return async_to_sync(value)()
+    return wrapped