diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index e5676a7a..951ebe15 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -1,3 +1,7 @@
+**1.1.1 - 06/17/24**
+
+ - Hotfix pin numpy below 2.0
+
 **1.1.0 - 05/29/24**
 
  - Adds out-of-core and distributed processing capability via Dask
diff --git a/setup.py b/setup.py
index 09b5d726..c01d5bdd 100644
--- a/setup.py
+++ b/setup.py
@@ -36,6 +36,7 @@
 
     install_requirements = [
         "pandas",
+        "numpy<2.0.0",
         "pyyaml>=5.1",
         "vivarium>=1.2.0",
         "pyarrow",