diff --git a/src/device.rs b/src/device.rs
index 2bed067c..8bcd8ed1 100644
--- a/src/device.rs
+++ b/src/device.rs
@@ -4,8 +4,6 @@ mod chain;
 mod launcher;
 mod looper;
 mod mixer;
-mod plugin;
-mod sampler;
 mod sequencer;
 mod track;
 mod transport;
@@ -13,26 +11,31 @@ mod transport;
 pub use self::track::Track;
 pub use self::launcher::{Launcher, Scene};
 pub use self::sequencer::{Sequencer, Phrase};
-pub use self::chain::Chain;
-pub use self::plugin::Plugin;
+pub use self::chain::{Chain, Sampler, Plugin};
 
 pub use self::looper::Looper;
 pub use self::mixer::Mixer;
-pub use self::sampler::Sampler;
 pub use self::transport::Transport;
 
 use crossterm::event;
 use ::jack::{Port, PortSpec, Client};
 
+/// A UI component that may have presence on the JACK grap.
 pub trait Device: Render + Handle + PortList + Send + Sync {
     fn boxed (self) -> Box<dyn Device> where Self: Sized + 'static {
         Box::new(self)
     }
 }
 
+/// All things that implement the required traits can be treated as `Device`.
+impl<T: Render + Handle + PortList + Send + Sync> Device for T {}
+
+/// Run a device as the root of the app.
 pub fn run (device: impl Device + Send + Sync + 'static) -> Result<(), Box<dyn Error>> {
     let device = Arc::new(Mutex::new(device));
     let exited = Arc::new(AtomicBool::new(false));
+
+    // Spawn input (handle) thread
     let _input_thread = {
         let poll = std::time::Duration::from_millis(100);
         let exited = exited.clone();
@@ -60,25 +63,23 @@ pub fn run (device: impl Device + Send + Sync + 'static) -> Result<(), Box<dyn E
             }
         })
     };
+
+    // Set up terminal
     stdout().execute(EnterAlternateScreen)?;
     enable_raw_mode()?;
     let mut terminal = ratatui::Terminal::new(CrosstermBackend::new(stdout()))?;
-    //better_panic::install();
+
+    // Set up panic hook
     let better_panic_handler = better_panic::Settings::auto()
         .verbosity(better_panic::Verbosity::Full)
         .create_panic_handler();
     std::panic::set_hook(Box::new(move |info: &std::panic::PanicInfo|{
-        stdout()
-            .execute(crossterm::terminal::LeaveAlternateScreen)
-            .unwrap();
-        crossterm::terminal::disable_raw_mode()
-            .unwrap();
+        stdout().execute(LeaveAlternateScreen).unwrap();
+        crossterm::terminal::disable_raw_mode().unwrap();
         better_panic_handler(info);
-        //writeln!(std::io::stderr(), "{}", info)
-            //.unwrap();
-        //writeln!(std::io::stderr(), "{:?}", ::backtrace::Backtrace::new())
-            //.unwrap();
     }));
+
+    // Main (render) loop
     let sleep = std::time::Duration::from_millis(16);
     loop {
         terminal.draw(|frame|{
@@ -91,28 +92,41 @@ pub fn run (device: impl Device + Send + Sync + 'static) -> Result<(), Box<dyn E
         }
         std::thread::sleep(sleep);
     };
-    //render_thread.join().expect("Failed to join render thread");
-    stdout()
-        .queue(crossterm::terminal::LeaveAlternateScreen)?
-        .flush()?;
+
+    // Cleanup
+    stdout().execute(LeaveAlternateScreen)?;
     crossterm::terminal::disable_raw_mode()?;
+
     Ok(())
 }
 
-impl<T: Render + Handle + PortList + Send + Sync> Device for T {}
-
-pub trait Named {
-}
-
+/// Trait for things that handle input events.
 pub trait Handle {
-    // Handle an input event.
-    // Returns Ok(true) if the device handled the event.
-    // This is the mechanism which allows nesting of components;.
+    /// Handle an input event.
+    /// Returns Ok(true) if the device handled the event.
+    /// This is the mechanism which allows nesting of components;.
     fn handle (&mut self, _e: &AppEvent) -> Usually<bool> {
         Ok(false)
     }
 }
 
+#[derive(Debug)]
+pub enum AppEvent {
+    /// Terminal input
+    Input(::crossterm::event::Event),
+    /// Update values but not the whole form.
+    Update,
+    /// Update the whole form.
+    Redraw,
+    /// Device gains focus
+    Focus,
+    /// Device loses focus
+    Blur,
+    /// JACK notification
+    Jack(JackEvent)
+}
+
+/// Trait for things that render to the display.
 pub trait Render {
     // Render something to an area of the buffer.
     // Returns area used by component.
@@ -122,6 +136,24 @@ pub trait Render {
     }
 }
 
+impl Render for Box<dyn Device> {
+    fn render (&self, b: &mut Buffer, a: Rect) -> Usually<Rect> {
+        (**self).render(b, a)
+    }
+}
+
+impl WidgetRef for &dyn Render {
+    fn render_ref (&self, area: Rect, buf: &mut Buffer) {
+        Render::render(*self, buf, area).expect("Failed to render device.");
+    }
+}
+
+impl WidgetRef for dyn Render {
+    fn render_ref (&self, area: Rect, buf: &mut Buffer) {
+        Render::render(self, buf, area).expect("Failed to render device.");
+    }
+}
+
 pub trait Blit {
     // Render something to X, Y coordinates in a buffer, ignoring width/height.
     fn blit (&self, buf: &mut Buffer, x: u16, y: u16, style: Option<Style>);
@@ -135,6 +167,7 @@ impl<T: AsRef<str>> Blit for T {
     }
 }
 
+/// Trait for things that may expose JACK ports.
 pub trait PortList {
     fn audio_ins  (&self) -> Usually<Vec<String>> {
         Ok(vec![])
@@ -163,12 +196,6 @@ pub trait PortList {
     }
 }
 
-impl Render for Box<dyn Device> {
-    fn render (&self, b: &mut Buffer, a: Rect) -> Usually<Rect> {
-        (**self).render(b, a)
-    }
-}
-
 pub struct DevicePort<T: PortSpec> {
     pub name:    String,
     pub port:    Port<T>,
@@ -189,18 +216,7 @@ impl<T: PortSpec + Default> DevicePort<T> {
     }
 }
 
-impl WidgetRef for &dyn Render {
-    fn render_ref (&self, area: Rect, buf: &mut Buffer) {
-        Render::render(*self, buf, area).expect("Failed to render device.");
-    }
-}
-
-impl WidgetRef for dyn Render {
-    fn render_ref (&self, area: Rect, buf: &mut Buffer) {
-        Render::render(self, buf, area).expect("Failed to render device.");
-    }
-}
-
+/// A device dynamicammy composed of state and handlers.
 pub struct DynamicDevice<T> {
     pub state:   Arc<Mutex<T>>,
     pub render:  Mutex<Box<dyn FnMut(&T, &mut Buffer, Rect)->Usually<Rect> + Send>>,
@@ -279,34 +295,6 @@ impl<T: Send + Sync + 'static> DynamicDevice<T> {
     }
 }
 
-#[derive(Debug)]
-pub enum AppEvent {
-    /// Terminal input
-    Input(::crossterm::event::Event),
-    /// Update values but not the whole form.
-    Update,
-    /// Update the whole form.
-    Redraw,
-    /// Device gains focus
-    Focus,
-    /// Device loses focus
-    Blur,
-    /// JACK notification
-    Jack(JackEvent)
-}
-
-fn panic_hook (info: &std::panic::PanicInfo) {
-    stdout()
-        .execute(crossterm::terminal::LeaveAlternateScreen)
-        .unwrap();
-    crossterm::terminal::disable_raw_mode()
-        .unwrap();
-    writeln!(std::io::stderr(), "{}", info)
-        .unwrap();
-    writeln!(std::io::stderr(), "{:?}", ::backtrace::Backtrace::new())
-        .unwrap();
-}
-
 #[derive(Debug)]
 pub enum JackEvent {
     ThreadInit,
diff --git a/src/device/chain.rs b/src/device/chain.rs
index 8a2d8e0d..f119588e 100644
--- a/src/device/chain.rs
+++ b/src/device/chain.rs
@@ -1,3 +1,8 @@
+mod plugin;
+pub use self::plugin::*;
+mod sampler;
+pub use self::sampler::*;
+
 use crate::prelude::*;
 
 pub struct Chain {
diff --git a/src/device/plugin.rs b/src/device/chain/plugin.rs
similarity index 100%
rename from src/device/plugin.rs
rename to src/device/chain/plugin.rs
diff --git a/src/device/plugin/lv2.rs b/src/device/chain/plugin/lv2.rs
similarity index 100%
rename from src/device/plugin/lv2.rs
rename to src/device/chain/plugin/lv2.rs
diff --git a/src/device/plugin/vst2.rs b/src/device/chain/plugin/vst2.rs
similarity index 100%
rename from src/device/plugin/vst2.rs
rename to src/device/chain/plugin/vst2.rs
diff --git a/src/device/plugin/vst3.rs b/src/device/chain/plugin/vst3.rs
similarity index 100%
rename from src/device/plugin/vst3.rs
rename to src/device/chain/plugin/vst3.rs
diff --git a/src/device/sampler.rs b/src/device/chain/sampler.rs
similarity index 100%
rename from src/device/sampler.rs
rename to src/device/chain/sampler.rs
diff --git a/src/device/patch.rs b/src/device/patch.rs
deleted file mode 100644
index e69de29b..00000000