diff --git a/egui_node_graph/src/editor_ui.rs b/egui_node_graph/src/editor_ui.rs
index 710a16e..a63f237 100644
--- a/egui_node_graph/src/editor_ui.rs
+++ b/egui_node_graph/src/editor_ui.rs
@@ -82,7 +82,7 @@ where
         &mut self,
         ui: &mut Ui,
         all_kinds: impl NodeTemplateIter<Item = NodeTemplate>,
-        user_state: &UserState,
+        user_state: &mut UserState,
     ) -> GraphResponse<UserResponse, NodeData> {
         // This causes the graph editor to use as much free space as it can.
         // (so for windows it will use up to the resizeably set limit
@@ -357,7 +357,7 @@ where
     pub fn show(
         self,
         ui: &mut Ui,
-        user_state: &UserState,
+        user_state: &mut UserState,
     ) -> Vec<NodeResponse<UserResponse, NodeData>> {
         let mut child_ui = ui.child_ui_with_id_source(
             Rect::from_min_size(*self.position + self.pan, Self::MAX_NODE_SIZE.into()),
@@ -373,7 +373,7 @@ where
     fn show_graph_node(
         self,
         ui: &mut Ui,
-        user_state: &UserState,
+        user_state: &mut UserState,
     ) -> Vec<NodeResponse<UserResponse, NodeData>> {
         let margin = egui::vec2(15.0, 5.0);
         let mut responses = Vec::<NodeResponse<UserResponse, NodeData>>::new();
@@ -468,7 +468,7 @@ where
             ui: &mut Ui,
             graph: &Graph<NodeData, DataType, ValueType>,
             node_id: NodeId,
-            user_state: &UserState,
+            user_state: &mut UserState,
             port_pos: Pos2,
             responses: &mut Vec<NodeResponse<UserResponse, NodeData>>,
             param_id: AnyParameterId,
diff --git a/egui_node_graph/src/traits.rs b/egui_node_graph/src/traits.rs
index ccf4388..8b90191 100644
--- a/egui_node_graph/src/traits.rs
+++ b/egui_node_graph/src/traits.rs
@@ -17,7 +17,7 @@ pub trait WidgetValueTrait {
 /// to the user.
 pub trait DataTypeTrait<UserState>: PartialEq + Eq {
     /// The associated port color of this datatype
-    fn data_type_color(&self, user_state: &UserState) -> egui::Color32;
+    fn data_type_color(&self, user_state: &mut UserState) -> egui::Color32;
 
     /// The name of this datatype. Return type is specified as Cow<str> because
     /// some implementations will need to allocate a new string to provide an
@@ -71,7 +71,7 @@ where
         ui: &mut egui::Ui,
         node_id: NodeId,
         graph: &Graph<Self, Self::DataType, Self::ValueType>,
-        user_state: &Self::UserState,
+        user_state: &mut Self::UserState,
     ) -> Vec<NodeResponse<Self::Response, Self>>
     where
         Self::Response: UserResponseTrait;
@@ -83,7 +83,7 @@ where
         _ui: &egui::Ui,
         _node_id: NodeId,
         _graph: &Graph<Self, Self::DataType, Self::ValueType>,
-        _user_state: &Self::UserState,
+        _user_state: &mut Self::UserState,
     ) -> Option<egui::Color32> {
         None
     }
@@ -126,7 +126,7 @@ pub trait NodeTemplateTrait: Clone {
     fn build_node(
         &self,
         graph: &mut Graph<Self::NodeData, Self::DataType, Self::ValueType>,
-        user_state: &Self::UserState,
+        user_state: &mut Self::UserState,
         node_id: NodeId,
     );
 }
diff --git a/egui_node_graph_example/src/app.rs b/egui_node_graph_example/src/app.rs
index 7a04a80..395d1aa 100644
--- a/egui_node_graph_example/src/app.rs
+++ b/egui_node_graph_example/src/app.rs
@@ -95,7 +95,7 @@ pub struct MyGraphState {
 
 // A trait for the data types, to tell the library how to display them
 impl DataTypeTrait<MyGraphState> for MyDataType {
-    fn data_type_color(&self, _user_state: &MyGraphState) -> egui::Color32 {
+    fn data_type_color(&self, _user_state: &mut MyGraphState) -> egui::Color32 {
         match self {
             MyDataType::Scalar => egui::Color32::from_rgb(38, 109, 211),
             MyDataType::Vec2 => egui::Color32::from_rgb(238, 207, 109),
@@ -143,7 +143,7 @@ impl NodeTemplateTrait for MyNodeTemplate {
     fn build_node(
         &self,
         graph: &mut Graph<Self::NodeData, Self::DataType, Self::ValueType>,
-        _user_state: &Self::UserState,
+        _user_state: &mut Self::UserState,
         node_id: NodeId,
     ) {
         // The nodes are created empty by default. This function needs to take
@@ -300,7 +300,7 @@ impl NodeDataTrait for MyNodeData {
         ui: &mut egui::Ui,
         node_id: NodeId,
         _graph: &Graph<MyNodeData, MyDataType, MyValueType>,
-        user_state: &Self::UserState,
+        user_state: &mut Self::UserState,
     ) -> Vec<NodeResponse<MyResponse, MyNodeData>>
     where
         MyResponse: UserResponseTrait,
@@ -394,7 +394,7 @@ impl eframe::App for NodeGraphExample {
         let graph_response = egui::CentralPanel::default()
             .show(ctx, |ui| {
                 self.state
-                    .draw_graph_editor(ui, AllMyNodeTemplates, &self.user_state)
+                    .draw_graph_editor(ui, AllMyNodeTemplates, &mut self.user_state)
             })
             .inner;
         for node_response in graph_response.node_responses {