diff --git a/requirements-dev.txt b/requirements-dev.txt
index e183619..8581d34 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -1,4 +1,4 @@
-numpy>=1.21.0
+numpy>=1.21.0, <2.0.0
 scipy>=1.8.0
 pylops>=2.0
 mpi4py