diff --git a/crates/tek_core/src/jack_core.rs b/crates/tek_core/src/jack_core.rs
index 56889364..7db017ac 100644
--- a/crates/tek_core/src/jack_core.rs
+++ b/crates/tek_core/src/jack_core.rs
@@ -144,7 +144,9 @@ impl Jack {
         })
     }
     pub fn run <D, T, U> (self, state: impl FnOnce(JackPorts)->Box<D>) -> Usually<JackDevice<T, U>>
-        where D: Device<T, U> + Process + Sized + 'static
+        where D: Device<T, U> + Process + Sized + 'static,
+              T: 'static,
+              U: 'static
     {
         let owned_ports = JackPorts {
             audio_ins:  register_ports(&self.client, self.audio_ins,  AudioIn)?,
diff --git a/crates/tek_core/src/render.rs b/crates/tek_core/src/render.rs
index 0471b1c0..7d5488c6 100644
--- a/crates/tek_core/src/render.rs
+++ b/crates/tek_core/src/render.rs
@@ -59,3 +59,14 @@ impl<R, T, U> Render<T, U> for RwLock<R> where R: Render<T, U> {
         self.read().unwrap().render(to)
     }
 }
+
+/// Boxed closures can be rendered.
+///
+/// Rendering unboxed closures should also be possible;
+/// but in practice implementing the trait for an unboxed
+/// `Fn` closure causes an impl conflict.
+impl<'a, T, U> Render<T, U> for Box<dyn Fn(&mut T) -> Perhaps<U> + Send + Sync + 'a> {
+    fn render (&self, to: &mut T) -> Perhaps<U> {
+        (*self)(to)
+    }
+}
diff --git a/crates/tek_core/src/render_border.rs b/crates/tek_core/src/render_border.rs
index bda9dda6..3b512a8c 100644
--- a/crates/tek_core/src/render_border.rs
+++ b/crates/tek_core/src/render_border.rs
@@ -28,11 +28,11 @@ pub trait BorderStyle {
         Ok(area)
     }
     #[inline]
-    fn draw_north (&self, buf: &mut Buffer, x: u16, y: u16, style: Option<Style>) -> Usually<Rect> {
+    fn draw_north (&self, buf: &mut Buffer, x: u16, y: u16, style: Option<Style>) -> Perhaps<Rect> {
         Self::N.blit(buf, x, y, style)
     }
     #[inline]
-    fn draw_south (&self, buf: &mut Buffer, x: u16, y: u16, style: Option<Style>) -> Usually<Rect> {
+    fn draw_south (&self, buf: &mut Buffer, x: u16, y: u16, style: Option<Style>) -> Perhaps<Rect> {
         Self::S.blit(buf, x, y, style)
     }
 
diff --git a/crates/tek_core/src/render_split.rs b/crates/tek_core/src/render_split.rs
index 03ba8848..d1ad21c9 100644
--- a/crates/tek_core/src/render_split.rs
+++ b/crates/tek_core/src/render_split.rs
@@ -60,34 +60,37 @@ impl<'a> Render<TuiOutput<'a>, Rect> for Split<'a, TuiOutput<'a>, Rect> {
     }
 }
 
-impl<'a> Split<'a, TuiOutput<'a>, Rect> {
-    pub fn render_areas (&self, to: &mut TuiOutput<'a>) -> Usually<(Rect, Vec<Rect>)> {
-        let Rect { mut x, mut y, mut width, mut height } = to.area;
-        let mut areas = vec![];
-        let buffer = &mut to.buffer;
-        for (index, item) in self.items.0.iter().enumerate() {
-            if width == 0 || height == 0 {
-                break
-            }
-            let target = TuiOutput { buffer, area: Rect { x, y, width, height } };
-            if let Some(result) = item.render(&mut target)? {
-                match self.direction {
-                    Direction::Down => {
-                        y += result.height;
-                        height = height.saturating_sub(result.height);
-                    },
-                    Direction::Right => {
-                        x += result.width;
-                        width = width.saturating_sub(result.width);
-                    },
-                    _ => unimplemented!()
-                };
-                areas.push(result);
-                if self.focus == Some(index) {
-                    Corners(Style::default().green().not_dim()).draw(buffer, result)?;
-                }
-            }
-        }
-        Ok((to.area, areas))
+impl<'a, 'b: 'a> Split<'a, TuiOutput<'a>, Rect> {
+    pub fn render_areas (&'a self, to: &mut TuiOutput<'a>) -> Usually<(Rect, Vec<Rect>)> {
+        Ok((Rect::default(), vec![]))
+        //let Rect { mut x, mut y, mut width, mut height } = to.area;
+        //let TuiOutput { buffer, area } = to;
+        //let mut areas = vec![];
+        //for (index, item) in self.items.0.iter().enumerate() {
+            //if width == 0 || height == 0 {
+                //break
+            //}
+            //if let Some(result) = item.render(&mut TuiOutput {
+                //buffer: to.buffer,
+                //area: Rect { x, y, width, height }
+            //})? {
+                //match self.direction {
+                    //Direction::Down => {
+                        //y += result.height;
+                        //height = height.saturating_sub(result.height);
+                    //},
+                    //Direction::Right => {
+                        //x += result.width;
+                        //width = width.saturating_sub(result.width);
+                    //},
+                    //_ => unimplemented!()
+                //};
+                //areas.push(result);
+                //if self.focus == Some(index) {
+                    //Corners(Style::default().green().not_dim()).draw(to.buffer, result)?;
+                //}
+            //}
+        //}
+        //Ok((to.area, areas))
     }
 }
diff --git a/crates/tek_core/src/render_tui.rs b/crates/tek_core/src/render_tui.rs
index f048d74b..45bfe780 100644
--- a/crates/tek_core/src/render_tui.rs
+++ b/crates/tek_core/src/render_tui.rs
@@ -8,29 +8,30 @@ pub struct TuiOutput<'a> {
 }
 
 /// Main thread render loop
-pub fn tui_render_thread <'a, T: Render<TuiOutput<'a>, Rect> + 'static> (
+pub fn tui_render_thread <'a: 'static, T> (
     exited: &Arc<AtomicBool>, device: &Arc<RwLock<T>>,
-) -> Usually<JoinHandle<()>> {
+) -> Usually<JoinHandle<()>> where
+    T: Render<TuiOutput<'a>, Rect> + 'static
+{
     let exited = exited.clone();
     let device = device.clone();
     let mut terminal = ratatui::Terminal::new(CrosstermBackend::new(stdout()))?;
     let sleep = Duration::from_millis(20);
-    Ok(spawn(move || loop {
-
-        if let Ok(device) = device.try_read() {
-            terminal.draw(|frame|{
-                let area = frame.size();
-                let buffer = frame.buffer_mut();
-                let mut output = TuiOutput { buffer, area };
-                device.render(&mut output).expect("Failed to render content");
-            })
-                .expect("Failed to render frame");
+    Ok(spawn(move || {
+        let draw = |frame: &'a mut ratatui::Frame|{
+            let area   = frame.size();
+            let buffer = frame.buffer_mut();
+            device.render(&mut TuiOutput { buffer, area }).expect("Failed to render content");
+        };
+        loop {
+            if let Ok(_) = device.try_read() {
+                terminal.draw(draw).expect("Failed to render frame");
+            }
+            if exited.fetch_and(true, Ordering::Relaxed) {
+                break
+            }
+            std::thread::sleep(sleep);
         }
-
-        if exited.fetch_and(true, Ordering::Relaxed) {
-            break
-        }
-        std::thread::sleep(sleep);
     }))
 }
 
@@ -76,19 +77,8 @@ impl<T: AsRef<str>> Blit for T {
 
 /// Rendering unit struct to Ratatui returns zero-sized [Rect] at render coordinates.
 impl<'a> Render<TuiOutput<'a>, Rect> for () {
-    fn render (&self, (_, area): (&mut Buffer, Rect)) -> Perhaps<Rect> {
-        Ok(Some(Rect { x: area.x, y: area.y, width: 0, height: 0 }))
-    }
-}
-
-/// Boxed closures can be rendered.
-/// 
-/// Rendering unboxed closures should also be possible;
-/// but in practice implementing the trait for an unboxed
-/// `Fn` closure causes an impl conflict.
-impl<'a, T, U> Render<T, U> for Box<dyn Fn(T) -> Usually<U> + Send + Sync + 'a> {
-    fn render (&self, to: T) -> Usually<U> {
-        (*self)(to)
+    fn render (&self, to: &mut TuiOutput<'a>) -> Perhaps<Rect> {
+        Ok(Some(Rect { x: to.area.x, y: to.area.y, width: 0, height: 0 }))
     }
 }