diff --git a/requirements.d/development.txt b/requirements.d/development.txt
index a8da71dcf..129331fbf 100644
--- a/requirements.d/development.txt
+++ b/requirements.d/development.txt
@@ -8,7 +8,7 @@ pytest
 pytest-xdist
 pytest-cov
 pytest-benchmark
-Cython
+Cython <3
 twine
 python-dateutil
 pre-commit