diff --git a/uvicorn/workers.py b/uvicorn/workers.py
index 1ac036372..e74065da0 100644
--- a/uvicorn/workers.py
+++ b/uvicorn/workers.py
@@ -13,7 +13,7 @@ class UvicornWorker(Worker):
     rather than a WSGI callable.
     """
 
-    CONFIG_KWARGS = {"loop": "uvloop", "http": "httptools"}
+    CONFIG_KWARGS = {"loop": "auto", "http": "auto"}
 
     def __init__(self, *args, **kwargs):
         super(UvicornWorker, self).__init__(*args, **kwargs)