diff --git a/human_eval/execution.py b/human_eval/execution.py
index d578771..5dc3926 100644
--- a/human_eval/execution.py
+++ b/human_eval/execution.py
@@ -161,7 +161,7 @@ def reliability_guard(maximum_memory_bytes: Optional[int] = None):
         import resource
         resource.setrlimit(resource.RLIMIT_AS, (maximum_memory_bytes, maximum_memory_bytes))
         resource.setrlimit(resource.RLIMIT_DATA, (maximum_memory_bytes, maximum_memory_bytes))
-        if not platform.uname().system == 'Darwin':
+        if platform.uname().system != 'Darwin':
             resource.setrlimit(resource.RLIMIT_STACK, (maximum_memory_bytes, maximum_memory_bytes))
 
     faulthandler.disable()