diff --git a/pyproject.toml b/pyproject.toml
index 06353c6682..6f4440c460 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -6,3 +6,9 @@ ignore = ["act/io/arm.py"]
 
 [tool.check-manifest]
 ignore = ["docs/*", "ci/*"]
+
+[tool.ruff]
+target-version = "py39"
+ignore = [
+    "E501",
+]