diff --git a/requirements-test.txt b/requirements-test.txt
index 6693f8d..94b4895 100644
--- a/requirements-test.txt
+++ b/requirements-test.txt
@@ -1,6 +1,6 @@
 # Test/lint dependencies for local dev and CI.
 pytest>=8,<10
 pypdf>=6.16.2,<7
-ruff>=0.9,<1
+ruff>=0.16.5,<1
 # OpenAPI contract validation for wm-serve (CI validates /openapi.json).
 openapi-spec-validator==0.9.0