diff --git a/pyproject.toml b/pyproject.toml
index 2b0e85a04..82ce83dab 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -9,6 +9,7 @@ requires = [
     "oldest-supported-numpy; python_version<'3.7'",
     # we need to build with at least 1.16.5 for a limited API bugfix
     "numpy==1.16.5; python_version=='3.7'",
-    "oldest-supported-numpy; python_version>='3.8'"
+    "oldest-supported-numpy; python_version=='3.8'",
+    "numpy>=2,<3; python_version>='3.9'",
 ]
 build-backend = "setuptools.build_meta"