diff --git a/requirements-dev.txt b/requirements-dev.txt
index f31b3c4..7e45d30 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -3,5 +3,5 @@ pytest>=9.1.1
 # Ruff is pinned exactly and must match the rev in .pre-commit-config.yaml:
 # formatter output differs between versions, so a skew reintroduces format
 # drift between local runs, pre-commit, and CI's `ruff format --check`.
-ruff==0.16.4
+ruff==0.16.9
 mypy>=2.3.1,<3