diff --git a/requirements/base.txt b/requirements/base.txt
index ac5158f..2f6bfc5 100644
--- a/requirements/base.txt
+++ b/requirements/base.txt
@@ -9,6 +9,9 @@ python-dateutil >=2.8.1,<3.0
 # pydantic: typed models and validation 
 pydantic >=2,<3
 
+# toml parsing if python <3.11
+toml >=0.10.2,<0.11
+
 # typer: typed command line interfaces.
 typer >=0.9,<0.10