diff --git a/src/core/sense.rs b/src/core/sense.rs
index cb3ad20..5a064a0 100644
--- a/src/core/sense.rs
+++ b/src/core/sense.rs
@@ -38,7 +38,7 @@ impl<W: WidgetLike<Tag>, Tag> Sensable<W::Widget, Tag> for W {
     {
         self.with_id(move |ui, id| {
             let id2 = id.clone();
-            ui.add(id.on(sense, move |ctx| f(&id2, ctx)))
+            ui.add(id.on(sense, move |ui| f(&id2, ui)))
         })
     }
     fn edit_on(
diff --git a/src/layout/sense.rs b/src/layout/sense.rs
index 4e44660..94c3e7e 100644
--- a/src/layout/sense.rs
+++ b/src/layout/sense.rs
@@ -43,6 +43,7 @@ pub struct SenseTrigger {
     pub shape: SenseShape,
     pub sense: Sense,
 }
+#[derive(Default)]
 pub struct SensorGroup {
     pub hover: ActivationState,
     pub cursor: ActivationState,
@@ -134,15 +135,6 @@ impl ActivationState {
     }
 }
 
-impl Default for SensorGroup {
-    fn default() -> Self {
-        Self {
-            hover: Default::default(),
-            cursor: Default::default(),
-            sensors: Default::default(),
-        }
-    }
-}
 impl Clone for SensorGroup {
     fn clone(&self) -> Self {
         Self {
diff --git a/src/lib.rs b/src/lib.rs
index 1935c7b..c8b54e5 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -7,7 +7,7 @@
 pub mod core;
 pub mod layout;
 pub mod render;
-mod util;
+pub mod util;
 
 pub mod prelude {
     pub use crate::core::*;
diff --git a/src/testing/app.rs b/src/testing/app.rs
index 36f1d7d..16c154f 100644
--- a/src/testing/app.rs
+++ b/src/testing/app.rs
@@ -1,4 +1,3 @@
-use ui::layout::Ui;
 use winit::{
     application::ApplicationHandler,
     event::WindowEvent,
@@ -10,7 +9,7 @@ use super::Client;
 
 #[derive(Default)]
 pub struct App {
-    client: Option<(Client, Ui)>,
+    client: Option<Client>,
 }
 
 impl App {
@@ -26,14 +25,13 @@ impl ApplicationHandler for App {
             let window = event_loop
                 .create_window(Window::default_attributes())
                 .unwrap();
-            let (ui, cui) = Client::create_ui();
-            let client = Client::new(window.into(), cui);
-            self.client = Some((client, ui));
+            let client = Client::new(window.into());
+            self.client = Some(client);
         }
     }
 
     fn window_event(&mut self, event_loop: &ActiveEventLoop, _id: WindowId, event: WindowEvent) {
-        let (client, ui) = self.client.as_mut().unwrap();
-        client.event(event, event_loop, ui);
+        let client = self.client.as_mut().unwrap();
+        client.event(event, event_loop);
     }
 }
diff --git a/src/testing/mod.rs b/src/testing/mod.rs
index 02452b8..2aff64d 100644
--- a/src/testing/mod.rs
+++ b/src/testing/mod.rs
@@ -18,16 +18,15 @@ pub fn main() {
 pub struct Client {
     renderer: Renderer,
     input: Input,
-    ui: ClientUi,
-}
-
-pub struct ClientUi {
+    ui: Ui,
     info: WidgetId<Text>,
     old_info: String,
 }
 
 impl Client {
-    pub fn create_ui() -> (Ui, ClientUi) {
+    pub fn new(window: Arc<Window>) -> Self {
+        let renderer = Renderer::new(window);
+
         let mut ui = Ui::new();
         let rect = Rect {
             color: UiColor::WHITE,
@@ -148,52 +147,44 @@ impl Client {
                 .span(Dir::DOWN, [fixed(40), ratio(1)])
                 .label("root"),
         );
-        (
-            ui,
-            ClientUi {
-                info,
-                old_info: String::new(),
-            },
-        )
-    }
 
-    pub fn new(window: Arc<Window>, ui: ClientUi) -> Self {
-        let renderer = Renderer::new(window);
         Self {
             renderer,
             input: Input::default(),
             ui,
+            info,
+            old_info: String::new(),
         }
     }
 
-    pub fn event(&mut self, event: WindowEvent, event_loop: &ActiveEventLoop, ui: &mut Ui) {
+    pub fn event(&mut self, event: WindowEvent, event_loop: &ActiveEventLoop) {
         self.input.event(&event);
         let cursor_state = self.cursor_state();
         let window_size = self.window_size();
-        ui.run_sensors(&cursor_state, window_size);
+        self.ui.run_sensors(&cursor_state, window_size);
         match event {
             WindowEvent::CloseRequested => event_loop.exit(),
             WindowEvent::RedrawRequested => {
-                ui.update();
-                self.renderer.update(ui);
+                self.ui.update();
+                self.renderer.update(&mut self.ui);
                 self.renderer.draw()
             }
             WindowEvent::Resized(size) => {
-                ui.resize((size.width, size.height));
+                self.ui.resize((size.width, size.height));
                 self.renderer.resize(&size)
             }
             _ => (),
         }
         let new = format!(
             "widgets: {}\nviews: {}",
-            ui.num_widgets(),
+            self.ui.num_widgets(),
             self.renderer.ui.view_count()
         );
-        if new != self.ui.old_info {
-            ui[&self.ui.info].content = new.clone();
-            self.ui.old_info = new;
+        if new != self.old_info {
+            self.ui[&self.info].content = new.clone();
+            self.old_info = new;
         }
-        if ui.needs_redraw() {
+        if self.ui.needs_redraw() {
             self.renderer.window().request_redraw();
         }
     }
diff --git a/src/util/mod.rs b/src/util/mod.rs
index 5cf9d68..3bcb269 100644
--- a/src/util/mod.rs
+++ b/src/util/mod.rs
@@ -2,9 +2,9 @@ mod id;
 mod math;
 mod refcount;
 
-pub use id::*;
-pub use math::*;
-pub use refcount::*;
+pub(crate) use id::*;
+pub(crate) use math::*;
+pub(crate) use refcount::*;
 
 pub type HashMap<K, V> = std::collections::HashMap<K, V>;
 pub type HashSet<K> = std::collections::HashSet<K>;