diff --git a/ribasim_qgis/core/nodes.py b/ribasim_qgis/core/nodes.py
index 45dfbb8e3..cbddfcef6 100644
--- a/ribasim_qgis/core/nodes.py
+++ b/ribasim_qgis/core/nodes.py
@@ -105,7 +105,7 @@ def set_defaults(self) -> None:
         defaults = getattr(self, "defaults", None)
         if self.layer is None or defaults is None:
             return
-        fields = self.layer._fields()
+        fields = self.layer.fields()
         for name, definition in defaults.items():
             index = fields.indexFromName(name)
             self.layer.setDefaultValueDefinition(index, definition)
@@ -113,7 +113,7 @@ def set_defaults(self) -> None:
     def set_dropdown(self, name: str, options: set[str]) -> None:
         """Use a dropdown menu for a field in the editor widget."""
         layer = self.layer
-        index = layer._fields().indexFromName(name)
+        index = layer.fields().indexFromName(name)
         setup = QgsEditorWidgetSetup(
             "ValueMap",
             {"map": {node: node for node in options}},
@@ -185,7 +185,7 @@ def write(self) -> None:
 
     def set_editor_widget(self) -> None:
         layer = self.layer
-        node_type_field = layer._fields().indexFromName("node_type")
+        node_type_field = layer.fields().indexFromName("node_type")
         self.set_dropdown("node_type", NONSPATIALNODETYPES)
 
         layer_form_config = layer.editFormConfig()
diff --git a/ribasim_qgis/core/topology.py b/ribasim_qgis/core/topology.py
index 4e365a7bb..fcb210426 100644
--- a/ribasim_qgis/core/topology.py
+++ b/ribasim_qgis/core/topology.py
@@ -49,7 +49,7 @@ def collect_node_properties(
     node: QgsVectorLayer,
 ) -> tuple[NDArray[np.float64], NDArray[np.int_], dict[str, tuple[str, int]]]:
     n_node = node.featureCount()
-    node_fields = node._fields()
+    node_fields = node.fields()
     type_field = node_fields.indexFromName("node_type")
     id_field = node_fields.indexFromName("node_id")
 
@@ -113,7 +113,7 @@ def set_edge_properties(node: QgsVectorLayer, edge: QgsVectorLayer) -> None:
     edge_xy = collect_edge_coordinates(edge)
     from_fid, to_fid = derive_connectivity(node_index, node_xy, edge_xy)
 
-    edge_fields = edge._fields()
+    edge_fields = edge.fields()
     from_type_field = edge_fields.indexFromName("from_node_type")
     from_id_field = edge_fields.indexFromName("from_node_id")
     to_type_field = edge_fields.indexFromName("to_node_type")