diff --git a/setup.py b/setup.py
index 435f72ed..382bb407 100644
--- a/setup.py
+++ b/setup.py
@@ -75,7 +75,7 @@ install_requires = [
     "dataclasses>=0.7, <1;python_version<'3.7'",
     "async_generator==1.10",
     "trio>=0.13.0",
-    "async-service>=0.1.0a2,<0.2.0",
+    "async-service>=0.1.0a4,<0.2.0",
     "async-exit-stack==1.0.1",
 ]