diff --git a/pyproject.toml b/pyproject.toml
index 7bc5ce9..8cf4bcd 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -51,7 +51,7 @@ mdeq = "mdeq:main"
 
 [project.optional-dependencies]
 test = ["pytest", "pytest-cov", "pytest-xdist", "nox"]
-dev = ["cogapp", "docformatter", "mdeq[test]", "ruff==0.15.20"]
+dev = ["cogapp", "docformatter", "mdeq[test]", "ruff==0.15.21"]
 
 [tool.pytest.ini_options]
 addopts = ["--strict-config", "-ra"]