diff --git a/requirements-dev.txt b/requirements-dev.txt
index 57ed9ed..1a1af29 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -1,4 +1,4 @@
 # Tooling for local development and CI (kept separate from the app runtime deps).
 pytest==9.1.1
 pytest-cov==7.1.0
-ruff==0.15.20
+ruff==0.15.21