diff --git a/pyproject.toml b/pyproject.toml
index 9b707de..c2b131d 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -35,7 +35,7 @@ dependencies = [
 ]
 
 [project.optional-dependencies]
-dev = ["pre-commit", "pytest", "pytest-cov", "pytest-mock", "ruff==0.14.14"]
+dev = ["pre-commit", "pytest", "pytest-cov", "pytest-mock", "ruff==0.15.5"]
 doc = ["sphinx", "pydata-sphinx-theme", "myst-parser", "autodoc_pydantic"]
 mcp = ["mcp[cli]>=1.2.0", "pyyaml"]
 
diff --git a/src/shift/mapper/edge_equipment_mapper.py b/src/shift/mapper/edge_equipment_mapper.py
index 89d0915..e4997f3 100644
--- a/src/shift/mapper/edge_equipment_mapper.py
+++ b/src/shift/mapper/edge_equipment_mapper.py
@@ -87,9 +87,9 @@ def _get_served_load(self, from_node: str, to_node: str) -> ApparentPower:
         descendants = list(nx.descendants(dfs_graph, parent_node))
         load_nodes = list(
             self.graph.get_nodes(
-                filter_func=lambda x: x.name in descendants
-                and x.assets is not None
-                and DistributionLoad in x.assets
+                filter_func=lambda x: (
+                    x.name in descendants and x.assets is not None and DistributionLoad in x.assets
+                )
             )
         )
         served_load = ApparentPower(0, "kilova")