diff --git a/pyproject.toml b/pyproject.toml
index 33bd3ed1..6d1fec40 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -74,6 +74,7 @@ dependencies = [
   # we need to install tomli.
   'tomli; python_version < "3.11"',
   "filelock>=3.20.3",
+  "GitPython",
 ]
 
 [project.optional-dependencies]