diff --git a/pyproject.toml b/pyproject.toml
index 0c4905f..6e25faa 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -31,7 +31,7 @@ dependencies = [
 "Source" = "https://github.com/OliverKillane/xmlable"
 
 [project.optional-dependencies]
-dev = ["black==23.11.0", "mypy==1.7.1", "pytest==7.4.3"]
+dev = ["black==23.12.0", "mypy==1.7.1", "pytest==7.4.3"]
 
 [tool.pytest.ini_options]
 minversion = "6.0"