diff --git a/pyproject.toml b/pyproject.toml
index d93549f..ce25551 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -102,7 +102,7 @@ optional-dependencies.develop = [
   "mypy<1.14",
   "poethepoet<0.30",
   "pyproject-fmt<2.5",
-  "ruff<0.8",
+  "ruff<0.9",
   "sphinx-autobuild==2021.3.14", # Newer versions stopped "watching" appropriately?
   "validate-pyproject<0.23",
 ]