diff --git a/pyproject.toml b/pyproject.toml
index d5d304e7..10167965 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -49,7 +49,7 @@ test = [
 lint = [
     # NOTE(ww): ruff is under active development, so we pin conservatively here
     # and let Dependabot periodically perform this update.
-    "ruff < 0.6.3",
+    "ruff < 0.6.4",
     # HACK(ww): interrogate needs setuptools to provide `pkg_resources` on Python 3.12+;
     # remove this when https://github.com/econchick/interrogate/issues/164 is resolved.
     "setuptools",