diff --git a/enable/__init__.py b/enable/__init__.py
index 2a8ad63a5..7164ed42d 100644
--- a/enable/__init__.py
+++ b/enable/__init__.py
@@ -16,7 +16,7 @@
     __version__ = "not-built"
 
 __requires__ = [
-    "numpy", "pillow", "traits>=6.2.0", "traitsui", "pyface>=7.2.0", "fonttools"
+    "numpy", "pillow<10", "traits>=6.2.0", "traitsui", "pyface>=7.2.0", "fonttools"
 ]
 
 __extras_require__ = {
diff --git a/pyproject.toml b/pyproject.toml
index 54d49e451..34c702732 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,3 +1,3 @@
 [build-system]
-requires = ["cython", "oldest-supported-numpy", "setuptools", "swig", "wheel"]
+requires = ["cython<3", "oldest-supported-numpy", "setuptools", "swig", "wheel"]
 build-backend = "setuptools.build_meta"