diff --git a/requirements_dev.txt b/requirements_dev.txt
index 04e171e..1663116 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -9,5 +9,5 @@ Sphinx==3.4.3
 pyyaml==5.4.1
 cryptography==3.3.2
 numpy==1.19.5
-Cython==0.29.21
+Cython==3.0.11
 pandas>=1.1.5