diff --git a/flake.nix b/flake.nix
index f8b81aa..ab969a4 100644
--- a/flake.nix
+++ b/flake.nix
@@ -20,6 +20,7 @@
             pytest-datadir
             pytest-mock
             pytest-subprocess
+            pytest-asyncio
             black
             mypy
             pylsp-mypy