diff --git a/pyproject.toml b/pyproject.toml
index 59a216bd..cb11a223 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -20,7 +20,7 @@ classifiers = [
 
 requires-python = ">=3.9"
 dependencies = [
-    "numpy",
+    "numpy<2.0",
     "scipy",
     "bottleneck",
     "toolz",