diff --git a/pyproject.toml b/pyproject.toml
index 0424c10..1f7cff9 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -7,7 +7,7 @@ include-package-data = true
 
 [project]
 name = "graphchem"
-version = "2.1.3"
+version = "2.1.4"
 authors = [
     { name="Travis Kessler", email="travis.j.kessler@gmail.com" },
 ]
@@ -18,6 +18,7 @@ dependencies = [
     "rdkit-pypi==2022.9.5",
     "torch==2.4.0",
     "torch-geometric==2.3.0",
+    "numpy==1.26.4"
 ]
 classifiers = [
     "Programming Language :: Python :: 3.11",