diff --git a/pyproject.toml b/pyproject.toml
index cbb0e8a..ea7d49d 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -50,6 +50,7 @@ dependencies = [
     "cdo",
     "cartopy",
     "vtk",
+    "pydantic",
     "richdem; python_version < '3.11'",
     "tomli; python_version < '3.11'",
 ]