diff --git a/pyproject.toml b/pyproject.toml
index 2bf5ec80..3cf9a28d 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,3 +1,3 @@
 [build-system]
-requires = ["setuptools", "wheel", "Cython"]
+requires = ["setuptools", "wheel", "Cython~=3.0a"]
 build-backend = "setuptools.build_meta"
diff --git a/setup.py b/setup.py
index 548b19f7..da4a66fa 100644
--- a/setup.py
+++ b/setup.py
@@ -81,7 +81,11 @@
     with_cython = True
 try:
     from Cython.Distutils.extension import Extension as _Extension
-    from Cython.Distutils import build_ext as _build_ext
+
+    try:
+        from Cython.Distutils.old_build_ext import old_build_ext as _build_ext
+    except ImportError:
+        from Cython.Distutils import build_ext as _build_ext
     with_cython = True
 except ImportError:
     if with_cython: