diff --git a/setup.cfg b/setup.cfg
index e8eecb4099e..60bf32b3c06 100755
--- a/setup.cfg
+++ b/setup.cfg
@@ -24,6 +24,7 @@ project_urls =
 packages = find:
 install_requires =
     aiorwlock==1.1.0
+    anyio<4.0.0
     appdirs>=1.4.4
     appdirs-stubs>=0.1.0
     async-generator>=1.10