diff --git a/requirements-dev.txt b/requirements-dev.txt
index 03f762f..8b1b2c2 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -13,3 +13,4 @@ flake8-import-order==0.18
 pytest==4.3.0
 pytest-cov==2.6.1
 codecov==2.0.15
+asynctest==0.12.2