diff --git a/pyproject.toml b/pyproject.toml
index ae65e48..9b984d3 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -22,6 +22,7 @@ classifiers = [
 dependencies = [
     "pargv>=0.2.0",
     "tomli>=1.1.0; python_version < '3.11'",
+    "tomli_w",
 ]
 dynamic = ["version", "description"]