diff --git a/pyproject.toml b/pyproject.toml
index d9067caf..80fdde9d 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -25,9 +25,11 @@ classifiers = [
   "Programming Language :: Python :: Implementation :: CPython",
   "Programming Language :: Python :: Implementation :: PyPy",
 ]
-urls.Source = "https://github.com/pypa/packaging"
 dependencies = []
 
+[project.urls]
+Source = "https://github.com/pypa/packaging"
+
 
 
 [tool.flit.sdist]