diff --git a/.github/workflows/conda/environment.yml b/.github/workflows/conda/environment.yml
index 8f791028c..1c0acbfce 100644
--- a/.github/workflows/conda/environment.yml
+++ b/.github/workflows/conda/environment.yml
@@ -16,5 +16,5 @@ dependencies:
   - eigen
   - simde
   - libmatio
-  - numpy
+  - numpy<2.4
   - scipy