diff --git a/src/arranger.rs b/src/arranger.rs
index efb6d39f..33e74002 100644
--- a/src/arranger.rs
+++ b/src/arranger.rs
@@ -22,7 +22,7 @@ pub struct ArrangerTui {
     pub size:     Measure<Tui>,
     pub note_buf: Vec<u8>,
     pub midi_buf: Vec<Vec<Vec<u8>>>,
-    pub editor:   MidiEditorModel,
+    pub editor:   MidiEditor,
     pub perf:     PerfModel,
 }
 impl ArrangerTui {
@@ -99,27 +99,29 @@ impl ArrangerTui {
         }
     }
 }
-render!(<Tui>|self: ArrangerTui|{
-    let play           = PlayPause(self.clock.is_rolling());
-    let transport      = TransportView::new(self, Some(ItemPalette::from(TuiTheme::g(96))), true);
-    let with_transport = |x|col!([row!(![&play, &transport]), &x]);
-    let pool_size      = if self.phrases.visible { self.splits[1] } else { 0 };
-    let with_pool      = |x|Split::w(false, pool_size, PoolView(&self.phrases), x);
-    let status         = ArrangerStatus::from(self);
-    let with_editbar   = |x|Split::n(false, 1, MidiEditStatus(&self.editor), x);
-    let with_status    = |x|Split::n(false, 2, status, x);
-    let with_size      = |x|lay!([&self.size, x]);
-    let arranger       = ||lay!(|add|{
-        let color = self.color;
-        add(&Fill::wh(Tui::bg(color.darkest.rgb, ())))?;
-        add(&Fill::wh(Outer(Style::default().fg(color.dark.rgb).bg(color.darkest.rgb))))?;
-        add(&Self::render_mode(self))
-    });
-    with_size(with_status(with_editbar(with_pool(with_transport(col!([
-        Fill::w(Fixed::h(20, arranger())),
-        Fill::wh(&self.editor),
-    ]))))))
-});
+impl Render<Tui> for ArrangerTui {
+    fn content (&self) -> Option<impl Render<Tui>> {
+        let play           = PlayPause(self.clock.is_rolling());
+        let transport      = TransportView::new(self, Some(ItemPalette::from(TuiTheme::g(96))), true);
+        let with_transport = |x|col!([row!(![&play, &transport]), &x]);
+        let pool_size      = if self.phrases.visible { self.splits[1] } else { 0 };
+        let with_pool      = |x|Split::w(false, pool_size, PoolView(&self.phrases), x);
+        let status         = ArrangerStatus::from(self);
+        let with_editbar   = |x|Split::n(false, 1, MidiEditStatus(&self.editor), x);
+        let with_status    = |x|Split::n(false, 2, status, x);
+        let with_size      = |x|lay!([&self.size, x]);
+        let arranger       = ||lay!(|add|{
+            let color = self.color;
+            add(&Fill::wh(Tui::bg(color.darkest.rgb, ())))?;
+            add(&Fill::wh(Outer(Style::default().fg(color.dark.rgb).bg(color.darkest.rgb))))?;
+            add(&Self::render_mode(self))
+        });
+        Some(with_size(with_status(with_editbar(with_pool(with_transport(col!([
+            Fill::w(Fixed::h(20, arranger())),
+            Fill::wh(&self.editor),
+        ])))))))
+    }
+}
 audio!(|self: ArrangerTui, client, scope|{
     // Start profiling cycle
     let t0 = self.perf.get_t0();
diff --git a/src/core/color.rs b/src/color.rs
similarity index 100%
rename from src/core/color.rs
rename to src/color.rs
diff --git a/src/core/command.rs b/src/command.rs
similarity index 100%
rename from src/core/command.rs
rename to src/command.rs
diff --git a/src/core.rs b/src/core.rs
index 40b42d85..e69de29b 100644
--- a/src/core.rs
+++ b/src/core.rs
@@ -1,69 +0,0 @@
-pub(crate) use std::error::Error;
-
-pub(crate) mod color;
-pub(crate) use color::*;
-pub use color::*;
-
-pub(crate) mod command; pub(crate) use command::*;
-pub(crate) mod engine;  pub(crate) use engine::*;
-pub(crate) mod focus;   pub(crate) use focus::*;
-pub(crate) mod input;   pub(crate) use input::*;
-pub(crate) mod output;  pub(crate) use output::*;
-
-pub(crate) use std::sync::atomic::{Ordering, AtomicBool, AtomicUsize};
-pub(crate) use Ordering::Relaxed;
-
-pub use self::{
-    engine::Engine,
-    input::Handle,
-    output::Render
-};
-
-/// Standard result type.
-pub type Usually<T> = Result<T, Box<dyn Error>>;
-
-/// Standard optional result type.
-pub type Perhaps<T> = Result<Option<T>, Box<dyn Error>>;
-
-/// Define test modules.
-#[macro_export] macro_rules! testmod {
-    ($($name:ident)*) => { $(#[cfg(test)] mod $name;)* };
-}
-
-/// Prototypal case of implementor macro.
-/// Saves 4loc per data pats.
-#[macro_export] macro_rules! from {
-    ($(<$($lt:lifetime),+>)?|$state:ident:$Source:ty|$Target:ty=$cb:expr) => {
-        impl $(<$($lt),+>)? From<$Source> for $Target {
-            fn from ($state:$Source) -> Self { $cb }
-        }
-    };
-}
-
-pub trait Gettable<T> {
-    /// Returns current value
-    fn get (&self) -> T;
-}
-
-pub trait Mutable<T>: Gettable<T> {
-    /// Sets new value, returns old
-    fn set (&mut self, value: T) -> T;
-}
-
-pub trait InteriorMutable<T>: Gettable<T> {
-    /// Sets new value, returns old
-    fn set (&self, value: T) -> T;
-}
-
-impl Gettable<bool> for AtomicBool {
-    fn get (&self) -> bool { self.load(Relaxed) }
-}
-impl InteriorMutable<bool> for AtomicBool {
-    fn set (&self, value: bool) -> bool { self.swap(value, Relaxed) }
-}
-impl Gettable<usize> for AtomicUsize {
-    fn get (&self) -> usize { self.load(Relaxed) }
-}
-impl InteriorMutable<usize> for AtomicUsize {
-    fn set (&self, value: usize) -> usize { self.swap(value, Relaxed) }
-}
diff --git a/src/core/test.rs b/src/core/test.rs
deleted file mode 100644
index 88699914..00000000
--- a/src/core/test.rs
+++ /dev/null
@@ -1,49 +0,0 @@
-#[cfg(test)] mod test_focus {
-    use super::focus::*;
-    #[test] fn test_focus () {
-
-        struct FocusTest {
-            focused: char,
-            cursor: (usize, usize)
-        }
-
-        impl HasFocus for FocusTest {
-            type Item = char;
-            fn focused (&self) -> Self::Item {
-                self.focused
-            }
-            fn set_focused (&mut self, to: Self::Item) {
-                self.focused = to
-            }
-        }
-
-        impl FocusGrid for FocusTest {
-            fn focus_cursor (&self) -> (usize, usize) {
-                self.cursor
-            }
-            fn focus_cursor_mut (&mut self) -> &mut (usize, usize) {
-                &mut self.cursor
-            }
-            fn focus_layout (&self) -> &[&[Self::Item]] {
-                &[
-                    &['a', 'a', 'a', 'b', 'b', 'd'],
-                    &['a', 'a', 'a', 'b', 'b', 'd'],
-                    &['a', 'a', 'a', 'c', 'c', 'd'],
-                    &['a', 'a', 'a', 'c', 'c', 'd'],
-                    &['e', 'e', 'e', 'e', 'e', 'e'],
-                ]
-            }
-        }
-
-        let mut tester = FocusTest { focused: 'a', cursor: (0, 0) };
-
-        tester.focus_right();
-        assert_eq!(tester.cursor.0, 3);
-        assert_eq!(tester.focused, 'b');
-
-        tester.focus_down();
-        assert_eq!(tester.cursor.1, 2);
-        assert_eq!(tester.focused, 'c');
-
-    }
-}
diff --git a/src/core/engine.rs b/src/engine.rs
similarity index 100%
rename from src/core/engine.rs
rename to src/engine.rs
diff --git a/src/event.rs b/src/event.rs
new file mode 100644
index 00000000..ea13af41
--- /dev/null
+++ b/src/event.rs
@@ -0,0 +1,34 @@
+use crate::*;
+
+pub struct EventMap<'a, const N: usize, E, T, U>(
+    pub [(E, &'a dyn Fn(T) -> U); N],
+    pub Option<&'a dyn Fn(T) -> U>,
+);
+
+impl<'a, const N: usize, E: PartialEq, T, U> EventMap<'a, N, E, T, U> {
+    pub fn handle (&self, context: T, event: &E) -> Option<U> {
+        for (binding, handler) in self.0.iter() {
+            if event == binding {
+                return Some(handler(context))
+            }
+        }
+        return None
+    }
+}
+
+#[macro_export] macro_rules! event_map {
+    ($events:expr) => {
+        EventMap($events, None)
+    };
+    ($events:expr, $default: expr) => {
+        EventMap($events, $default)
+    };
+}
+
+#[macro_export] macro_rules! event_map_input_to_command {
+    ($Engine:ty: $Model:ty: $Command:ty: $EventMap:expr) => {
+        input_to_command!($Command: <$Engine>|state: $Model, input|{
+            event_map!($EventMap).handle(state, input.event())?
+        });
+    }
+}
diff --git a/src/tui/file_browser.rs b/src/file.rs
similarity index 100%
rename from src/tui/file_browser.rs
rename to src/file.rs
diff --git a/src/core/focus.rs b/src/focus.rs
similarity index 100%
rename from src/core/focus.rs
rename to src/focus.rs
diff --git a/src/groovebox.rs b/src/groovebox.rs
index f8a6753a..94f63393 100644
--- a/src/groovebox.rs
+++ b/src/groovebox.rs
@@ -2,7 +2,7 @@ use crate::*;
 use super::*;
 use KeyCode::{Char, Delete, Tab, Up, Down, Left, Right};
 use ClockCommand::{Play, Pause};
-use GrooveboxCommand::*;
+use GrooveboxCommand as Cmd;
 use PhraseCommand::*;
 use PhrasePoolCommand::*;
 
@@ -11,7 +11,7 @@ pub struct Groovebox {
 
     pub player:    MidiPlayer,
     pub pool:      PoolModel,
-    pub editor:    MidiEditorModel,
+    pub editor:    MidiEditor,
     pub sampler:   Sampler,
 
     pub size:      Measure<Tui>,
@@ -49,7 +49,7 @@ impl Groovebox {
         )));
         player.play_phrase = Some((Moment::zero(&player.clock.timebase), Some(phrase.clone())));
         let pool    = crate::pool::PoolModel::from(&phrase);
-        let editor  = crate::midi::MidiEditorModel::from(&phrase);
+        let editor  = crate::midi::MidiEditor::from(&phrase);
         Ok(Self {
             _jack:    jack.clone(),
             player,
@@ -142,25 +142,29 @@ render!(<Tui>|self:Groovebox|{
 });
 
 struct EditStatus<'a, T: Render<Tui>>(&'a Sampler, &'a MidiEditor, usize, T);
-render!(<Tui>|self: EditStatus<'a, T: Render<Tui>>|Split::n(false, 9, col!(![
-    row!(|add|{
-        if let Some(sample) = &self.0.mapped[self.2] {
-            add(&format!("Sample {}", sample.read().unwrap().end))?;
-        }
-        add(&MidiEditStatus(&self.1))?;
-        Ok(())
-    }),
-    lay!([
-        Outer(Style::default().fg(TuiTheme::g(128))),
-        Fill::w(Fixed::h(8, if let Some((_, sample)) = &self.0.recording {
-            SampleViewer(Some(sample.clone()))
-        } else if let Some(sample) = &self.0.mapped[self.2] {
-            SampleViewer(Some(sample.clone()))
-        } else {
-            SampleViewer(None)
-        })),
-    ]),
-]), self.3));
+impl<'a, T: Render<Tui>> Render<Tui> for EditStatus<'a, T> {
+    fn content (&self) -> impl Render<Tui> {
+        Split::n(false, 9, col!([
+            row!(|add|{
+                if let Some(sample) = &self.0.mapped[self.2] {
+                    add(&format!("Sample {}", sample.read().unwrap().end))?;
+                }
+                add(&MidiEditStatus(&self.1))?;
+                Ok(())
+            }),
+            lay!([
+                Outer(Style::default().fg(TuiTheme::g(128))),
+                Fill::w(Fixed::h(8, if let Some((_, sample)) = &self.0.recording {
+                    SampleViewer(Some(sample.clone()))
+                } else if let Some(sample) = &self.0.mapped[self.2] {
+                    SampleViewer(Some(sample.clone()))
+                } else {
+                    SampleViewer(None)
+                })),
+            ]),
+        ]), &self.3)
+    }
+}
 
 struct GrooveboxSamples<'a>(&'a Groovebox);
 render!(<Tui>|self: GrooveboxSamples<'a>|{
@@ -204,19 +208,19 @@ input_to_command!(GrooveboxCommand: <Tui>|state: Groovebox, input|match input.ev
     },
 
     // Transport: Play from start or rewind to start
-    key_pat!(Char(' ')) => Clock(
+    key_pat!(Char(' ')) => Cmd::Clock(
         if state.clock().is_stopped() { Play(Some(0)) } else { Pause(Some(0)) }
     ),
 
     // Tab: Toggle visibility of phrase pool column
-    key_pat!(Tab) => Pool(PoolCommand::Show(!state.pool.visible)),
+    key_pat!(Tab) => Cmd::Pool(PoolCommand::Show(!state.pool.visible)),
 
     // q: Enqueue currently edited phrase
-    key_pat!(Char('q')) => Enqueue(Some(state.pool.phrase().clone())),
+    key_pat!(Char('q')) => Cmd::Enqueue(Some(state.pool.phrase().clone())),
     // 0: Enqueue phrase 0 (stop all)
-    key_pat!(Char('0')) => Enqueue(Some(state.pool.phrases()[0].clone())),
+    key_pat!(Char('0')) => Cmd::Enqueue(Some(state.pool.phrases()[0].clone())),
 
-    key_pat!(Shift-Char('R')) => Sampler(if state.sampler.recording.is_some() {
+    key_pat!(Shift-Char('R')) => Cmd::Sampler(if state.sampler.recording.is_some() {
         SamplerCommand::RecordFinish
     } else {
         SamplerCommand::RecordBegin(u7::from(state.editor.note_point() as u8))
@@ -226,7 +230,7 @@ input_to_command!(GrooveboxCommand: <Tui>|state: Groovebox, input|match input.ev
     key_pat!(Char('e')) => if let Some((_, Some(playing))) = state.player.play_phrase() {
         let editing  = state.editor.phrase().as_ref().map(|p|p.read().unwrap().clone());
         let selected = state.pool.phrase().clone();
-        Editor(Show(Some(if Some(selected.read().unwrap().clone()) != editing {
+        Cmd::Editor(Show(Some(if Some(selected.read().unwrap().clone()) != editing {
             selected
         } else {
             playing.clone()
@@ -238,9 +242,9 @@ input_to_command!(GrooveboxCommand: <Tui>|state: Groovebox, input|match input.ev
     // For the rest, use the default keybindings of the components.
     // The ones defined above supersede them.
     _ => if let Some(command) = PhraseCommand::input_to_command(&state.editor, input) {
-        Editor(command)
+        Cmd::Editor(command)
     } else if let Some(command) = PoolCommand::input_to_command(&state.pool, input) {
-        Pool(command)
+        Cmd::Pool(command)
     } else {
         return None
     }
@@ -250,7 +254,7 @@ command!(|self: GrooveboxCommand, state: Groovebox|match self {
     Self::Pool(cmd) => {
         let mut default = |cmd: PoolCommand|cmd
             .execute(&mut state.pool)
-            .map(|x|x.map(Pool));
+            .map(|x|x.map(Self::Pool));
         match cmd {
             // autoselect: automatically load selected phrase in editor
             PoolCommand::Select(_) => {
@@ -268,13 +272,13 @@ command!(|self: GrooveboxCommand, state: Groovebox|match self {
         }
     },
     Self::Editor(cmd) => {
-        let default = ||cmd.execute(&mut state.editor).map(|x|x.map(Editor));
+        let default = ||cmd.execute(&mut state.editor).map(|x|x.map(Self::Editor));
         match cmd {
             _ => default()?
         }
     },
-    Self::Clock(cmd) => cmd.execute(state)?.map(Clock),
-    Self::Sampler(cmd) => cmd.execute(&mut state.sampler)?.map(Sampler),
+    Self::Clock(cmd) => cmd.execute(state)?.map(Self::Clock),
+    Self::Sampler(cmd) => cmd.execute(&mut state.sampler)?.map(Self::Sampler),
     Self::Enqueue(phrase) => {
         state.player.enqueue_next(phrase.as_ref());
         None
diff --git a/src/core/input.rs b/src/input.rs
similarity index 100%
rename from src/core/input.rs
rename to src/input.rs
diff --git a/src/lib.rs b/src/lib.rs
index 01258fc5..60204b0e 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,69 +1,50 @@
 #![allow(unused)]
 #![allow(clippy::unit_arg)]
 
-pub mod core; pub use self::core::*;
-
-pub mod time; pub(crate) use self::time::*;
-pub use self::time::HasClock;
-
-pub mod space; pub(crate) use self::space::*;
-pub use self::space::Measure;
-
-pub mod tui; pub(crate) use self::tui::*;
-pub use tui::*;
-
-pub mod jack; pub(crate) use self::jack::*;
-pub use self::jack::*;
-
-pub mod midi; pub(crate) use self::midi::*;
-
-pub mod meter; pub(crate) use self::meter::*;
-
-pub mod piano_h; pub(crate) use self::piano_h::*; 
-
-pub mod transport; pub(crate) use self::transport::*;
-pub use self::transport::TransportTui;
-
-pub mod sequencer; pub(crate) use self::sequencer::*;
-pub use self::sequencer::SequencerTui;
-
-pub mod arranger; pub(crate) use self::arranger::*;
-pub use self::arranger::ArrangerTui;
-
-pub mod sampler; pub(crate) use self::sampler::*;
-pub use self::sampler::{SamplerTui, Sampler, Sample, Voice};
-
-pub mod mixer; pub(crate) use self::mixer::*;
-pub use self::mixer::{Mixer, MixerTrack, MixerTrackDevice};
-
-pub mod plugin; pub(crate) use self::plugin::*;
-pub use self::plugin::*;
-
-pub mod groovebox; pub(crate) use self::groovebox::*;
-pub use self::groovebox::Groovebox;
-
-pub mod pool; pub(crate) use self::pool::*;
-pub use self::pool::PoolModel;
-
-pub mod status; pub(crate) use self::status::*;
-
-pub use ::better_panic; pub(crate) use better_panic::{Settings, Verbosity};
-
-pub use ::atomic_float; pub(crate) use atomic_float::*;
-
-pub(crate) use std::sync::{Arc, Mutex, RwLock};
-pub(crate) use std::sync::atomic::Ordering;
-pub(crate) use std::sync::atomic::{AtomicBool, AtomicUsize};
-pub(crate) use std::collections::BTreeMap;
-pub(crate) use std::marker::PhantomData;
-pub(crate) use std::thread::{spawn, JoinHandle};
-pub(crate) use std::path::PathBuf;
-pub(crate) use std::ffi::OsString;
-pub(crate) use std::time::Duration;
-pub(crate) use std::io::{Stdout, stdout};
-pub(crate) use std::ops::{Add, Sub, Mul, Div, Rem};
 pub(crate) use std::cmp::{Ord, Eq, PartialEq};
+pub(crate) use std::collections::BTreeMap;
+pub(crate) use std::error::Error;
+pub(crate) use std::ffi::OsString;
 pub(crate) use std::fmt::{Debug, Display, Formatter};
+pub(crate) use std::io::{Stdout, stdout};
+pub(crate) use std::marker::PhantomData;
+pub(crate) use std::ops::{Add, Sub, Mul, Div, Rem};
+pub(crate) use std::path::PathBuf;
+pub(crate) use std::sync::atomic::{AtomicBool, AtomicUsize, Ordering::{self, *}};
+pub(crate) use std::sync::{Arc, Mutex, RwLock};
+pub(crate) use std::thread::{spawn, JoinHandle};
+pub(crate) use std::time::Duration;
+
+pub mod arranger;  pub use self::arranger::*;
+pub mod color;     pub use self::color::*;
+pub mod command;   pub use self::command::*;
+pub mod engine;    pub use self::engine::*;
+pub mod event;     pub use self::event::*;
+pub mod file;      pub use self::file::*;
+pub mod focus;     pub use self::focus::*;
+pub mod groovebox; pub use self::groovebox::*;
+pub mod input;     pub use self::input::*;
+pub mod jack;      pub use self::jack::*;
+pub mod meter;     pub use self::meter::*;
+pub mod midi;      pub use self::midi::*;
+pub mod mixer;     pub use self::mixer::*;
+pub mod output;    pub use self::output::*;
+pub mod piano_h;   pub use self::piano_h::*; 
+pub mod plugin;    pub use self::plugin::*;
+pub mod pool;      pub use self::pool::*;
+pub mod sampler;   pub use self::sampler::*;
+pub mod sequencer; pub use self::sequencer::*;
+pub mod space;     pub use self::space::*;
+pub mod status;    pub use self::status::*;
+pub mod time;      pub use self::time::*;
+pub mod transport; pub use self::transport::*;
+pub mod tui;       pub use self::tui::*;
+
+pub use ::better_panic;
+pub(crate) use better_panic::{Settings, Verbosity};
+
+pub use ::atomic_float;
+pub(crate) use atomic_float::*;
 
 pub use ::crossterm;
 pub(crate) use crossterm::{ExecutableCommand};
@@ -93,3 +74,55 @@ pub(crate) use ::palette::{
 };
 
 testmod! { test }
+
+/// Standard result type.
+pub type Usually<T> = Result<T, Box<dyn Error>>;
+
+/// Standard optional result type.
+pub type Perhaps<T> = Result<Option<T>, Box<dyn Error>>;
+
+/// Define test modules.
+#[macro_export] macro_rules! testmod {
+    ($($name:ident)*) => { $(#[cfg(test)] mod $name;)* };
+}
+
+/// Prototypal case of implementor macro.
+/// Saves 4loc per data pats.
+#[macro_export] macro_rules! from {
+    ($(<$($lt:lifetime),+>)?|$state:ident:$Source:ty|$Target:ty=$cb:expr) => {
+        impl $(<$($lt),+>)? From<$Source> for $Target {
+            fn from ($state:$Source) -> Self { $cb }
+        }
+    };
+}
+
+pub trait Gettable<T> {
+    /// Returns current value
+    fn get (&self) -> T;
+}
+
+pub trait Mutable<T>: Gettable<T> {
+    /// Sets new value, returns old
+    fn set (&mut self, value: T) -> T;
+}
+
+pub trait InteriorMutable<T>: Gettable<T> {
+    /// Sets new value, returns old
+    fn set (&self, value: T) -> T;
+}
+
+impl Gettable<bool> for AtomicBool {
+    fn get (&self) -> bool { self.load(Relaxed) }
+}
+
+impl InteriorMutable<bool> for AtomicBool {
+    fn set (&self, value: bool) -> bool { self.swap(value, Relaxed) }
+}
+
+impl Gettable<usize> for AtomicUsize {
+    fn get (&self) -> usize { self.load(Relaxed) }
+}
+
+impl InteriorMutable<usize> for AtomicUsize {
+    fn set (&self, value: usize) -> usize { self.swap(value, Relaxed) }
+}
diff --git a/src/midi/midi_editor.rs b/src/midi/midi_editor.rs
index f61779b1..72e79c59 100644
--- a/src/midi/midi_editor.rs
+++ b/src/midi/midi_editor.rs
@@ -3,13 +3,13 @@ use KeyCode::{Char, Up, Down, Left, Right, Enter};
 use PhraseCommand::*;
 
 pub trait HasEditor {
-    fn editor (&self) -> &MidiEditorModel;
+    fn editor (&self) -> &MidiEditor;
 }
 
 #[macro_export] macro_rules! has_editor {
     (|$self:ident:$Struct:ident$(<$($L:lifetime),*$($T:ident$(:$U:path)?),*>)?|$cb:expr) => {
         impl $(<$($L),*$($T $(: $U)?),*>)? HasEditor for $Struct $(<$($L),*$($T),*>)? {
-            fn editor (&$self) -> &MidiEditorModel { &$cb }
+            fn editor (&$self) -> &MidiEditor { &$cb }
         }
     }
 }
@@ -29,8 +29,8 @@ pub enum PhraseCommand {
     Show(Option<Arc<RwLock<MidiClip>>>),
 }
 
-event_map_input_to_command!(Tui: MidiEditorModel: PhraseCommand: MidiEditorModel::KEYS);
-impl MidiEditorModel {
+event_map_input_to_command!(Tui: MidiEditor: PhraseCommand: MidiEditor::KEYS);
+impl MidiEditor {
     const KEYS: KeyMapping<31, Self> = [
         (kexp!(Ctrl-Alt-Up),    &|s: &Self|SetNoteScroll(s.note_point() + 3)),
         (kexp!(Ctrl-Alt-Down),  &|s: &Self|SetNoteScroll(s.note_point().saturating_sub(3))),
@@ -71,8 +71,8 @@ impl MidiEditorModel {
     }
 }
 
-impl Command<MidiEditorModel> for PhraseCommand {
-    fn execute (self, state: &mut MidiEditorModel) -> Perhaps<Self> {
+impl Command<MidiEditor> for PhraseCommand {
+    fn execute (self, state: &mut MidiEditor) -> Perhaps<Self> {
         use PhraseCommand::*;
         match self {
             Show(phrase)        => { state.set_phrase(phrase.as_ref());   },
@@ -92,13 +92,13 @@ impl Command<MidiEditorModel> for PhraseCommand {
 }
 
 /// Contains state for viewing and editing a phrase
-pub struct MidiEditorModel {
+pub struct MidiEditor {
     /// Renders the phrase
     pub mode: Box<dyn PhraseViewMode>,
     pub size: Measure<Tui>
 }
 
-impl Default for MidiEditorModel {
+impl Default for MidiEditor {
     fn default () -> Self {
         let mut mode = Box::new(PianoHorizontal::new(None));
         mode.redraw();
@@ -106,13 +106,13 @@ impl Default for MidiEditorModel {
     }
 }
 
-has_size!(<Tui>|self:MidiEditorModel|&self.size);
-render!(<Tui>|self: MidiEditorModel|{
+has_size!(<Tui>|self: MidiEditor|&self.size);
+render!(<Tui>|self: MidiEditor|{
     self.autoscroll();
     self.autozoom();
     &self.mode
 });
-//render!(<Tui>|self: MidiEditorModel|lay!(|add|{add(&self.size)?;add(self.mode)}));//bollocks
+//render!(<Tui>|self: MidiEditor|lay!(|add|{add(&self.size)?;add(self.mode)}));//bollocks
 
 pub trait PhraseViewMode: Render<Tui> + HasSize<Tui> + MidiRange + MidiPoint + Debug + Send + Sync {
     fn buffer_size (&self, phrase: &MidiClip) -> (usize, usize);
@@ -125,9 +125,9 @@ pub trait PhraseViewMode: Render<Tui> + HasSize<Tui> + MidiRange + MidiPoint + D
     }
 }
 
-impl MidiView<Tui> for MidiEditorModel {}
+impl MidiView<Tui> for MidiEditor {}
 
-impl TimeRange for MidiEditorModel {
+impl TimeRange for MidiEditor {
     fn time_len   (&self) -> &AtomicUsize { self.mode.time_len()   }
     fn time_zoom  (&self) -> &AtomicUsize { self.mode.time_zoom()  }
     fn time_lock  (&self) -> &AtomicBool  { self.mode.time_lock()  }
@@ -135,24 +135,24 @@ impl TimeRange for MidiEditorModel {
     fn time_axis  (&self) -> &AtomicUsize { self.mode.time_axis()  }
 }
 
-impl NoteRange for MidiEditorModel {
+impl NoteRange for MidiEditor {
     fn note_lo    (&self) -> &AtomicUsize { self.mode.note_lo()    }
     fn note_axis  (&self) -> &AtomicUsize { self.mode.note_axis()  }
 }
 
-impl NotePoint for MidiEditorModel {
+impl NotePoint for MidiEditor {
     fn note_len (&self) -> usize { self.mode.note_len() }
     fn set_note_len (&self, x: usize) { self.mode.set_note_len(x) }
     fn note_point (&self) -> usize { self.mode.note_point() }
     fn set_note_point (&self, x: usize) { self.mode.set_note_point(x) }
 }
 
-impl TimePoint for MidiEditorModel {
+impl TimePoint for MidiEditor {
     fn time_point (&self) -> usize { self.mode.time_point() }
     fn set_time_point (&self, x: usize) { self.mode.set_time_point(x) }
 }
 
-impl PhraseViewMode for MidiEditorModel {
+impl PhraseViewMode for MidiEditor {
     fn buffer_size (&self, phrase: &MidiClip) -> (usize, usize) {
         self.mode.buffer_size(phrase)
     }
@@ -170,7 +170,7 @@ impl PhraseViewMode for MidiEditorModel {
     }
 }
 
-impl MidiEditorModel {
+impl MidiEditor {
     /// Put note at current position
     pub fn put_note (&mut self, advance: bool) {
         let mut redraw = false;
@@ -203,22 +203,22 @@ impl MidiEditorModel {
     }
 }
 
-from!(|phrase: &Arc<RwLock<MidiClip>>|MidiEditorModel = {
+from!(|phrase: &Arc<RwLock<MidiClip>>|MidiEditor = {
     let mut model = Self::from(Some(phrase.clone()));
     model.redraw();
     model
 });
 
-from!(|phrase: Option<Arc<RwLock<MidiClip>>>|MidiEditorModel = {
+from!(|phrase: Option<Arc<RwLock<MidiClip>>>|MidiEditor = {
     let mut model = Self::default();
     *model.phrase_mut() = phrase;
     model.redraw();
     model
 });
 
-impl std::fmt::Debug for MidiEditorModel {
+impl std::fmt::Debug for MidiEditor {
     fn fmt (&self, f: &mut std::fmt::Formatter<'_>) -> std::result::Result<(), std::fmt::Error> {
-        f.debug_struct("MidiEditorModel")
+        f.debug_struct("MidiEditor")
             .field("mode", &self.mode)
             .finish()
     }
diff --git a/src/core/output.rs b/src/output.rs
similarity index 79%
rename from src/core/output.rs
rename to src/output.rs
index ff8748a7..5a45e89e 100644
--- a/src/core/output.rs
+++ b/src/output.rs
@@ -1,13 +1,24 @@
 use crate::*;
 
+/// Ad-hoc widget with custom rendering.
+pub fn render <E, F> (render: F) -> impl Render<E>
+    where E: Engine, F: Fn(&mut E::Output)->Usually<()>+Send+Sync
+{
+    Widget::new(|_|Ok(Some([0.into(),0.into()].into())), render)
+}
+
+/// Cast to dynamic pointer
+pub fn widget <E, T> (w: &T) -> &dyn Render<E>
+    where E: Engine, T: Render<E>
+{
+    w as &dyn Render<E>
+}
+
 #[macro_export] macro_rules! render {
     (|$self:ident:$Struct:ident$(<$($L:lifetime),*E$(,$T:ident$(:$U:path)?)*$(,)?>)?|$cb:expr) => {
         impl<E: Engine, $($($L),*$($T $(: $U)?),*)?> Render<E> for $Struct $(<$($L,)* E, $($T),*>)? {
-            fn min_size (&$self, to: <E as Engine>::Size) -> Perhaps<<E as Engine>::Size> {
-                $cb.min_size(to)
-            }
-            fn render (&$self, to: &mut <E as Engine>::Output) -> Usually<()> {
-                $cb.render(to)
+            fn content (&$self) -> Option<impl Render<$E>> {
+                Some($cb)
             }
         }
     };
@@ -22,11 +33,8 @@ use crate::*;
             $($($L),+)?
             $($($T),+)?
         >)? {
-            fn min_size (&$self, to: <$E as Engine>::Size) -> Perhaps<<$E as Engine>::Size> {
-                $cb.min_size(to)
-            }
-            fn render (&$self, to: &mut <$E as Engine>::Output) -> Usually<()> {
-                $cb.render(to)
+            fn content (&$self) -> Option<impl Render<$E>> {
+                Some($cb)
             }
         }
     }
@@ -42,19 +50,28 @@ pub trait Output<E: Engine> {
     fn render_in (&mut self, area: E::Area, widget: &dyn Render<E>) -> Usually<()>;
 }
 
-/// Cast to dynamic pointer
-pub fn widget <E: Engine, T: Render<E>> (w: &T) -> &dyn Render<E> {
-    w as &dyn Render<E>
-}
-
 /// A renderable component
-pub trait Render<E: Engine>: Send + Sync {
+pub trait Render<E: Engine>: Send + Sync where (): Render<E> {
+    fn content (&self) -> Option<impl Render<E>> where Self: Sized {
+        None::<()>
+    }
     /// Minimum size to use
     fn min_size (&self, to: E::Size) -> Perhaps<E::Size> {
-        Ok(Some(to))
+        self.content().map(|content|content.min_size(to)).unwrap_or(Ok(None))
     }
     /// Draw to output render target
-    fn render (&self, to: &mut E::Output) -> Usually<()>;
+    fn render (&self, to: &mut E::Output) -> Usually<()> {
+        self.content().map(|content|content.render(to)).unwrap_or(Ok(()))
+    }
+}
+
+impl<E: Engine> Render<E> for () {
+    fn min_size (&self, to: E::Size)  -> Perhaps<E::Size> {
+        Ok(None)
+    }
+    fn render (&self, to: &mut E::Output) -> Usually<()> {
+        Ok(())
+    }
 }
 
 impl<E: Engine, R: Render<E>> Render<E> for &R {
diff --git a/src/sequencer.rs b/src/sequencer.rs
index b9dc4287..fdfa6cc5 100644
--- a/src/sequencer.rs
+++ b/src/sequencer.rs
@@ -12,7 +12,7 @@ pub struct SequencerTui {
     pub clock:     ClockModel,
     pub phrases:   PoolModel,
     pub player:    MidiPlayer,
-    pub editor:    MidiEditorModel,
+    pub editor:    MidiEditor,
     pub size:      Measure<Tui>,
     pub status:    bool,
     pub note_buf:  Vec<u8>,
@@ -30,7 +30,7 @@ from_jack!(|jack|SequencerTui {
         transport: true,
         selectors: true,
         phrases:   PoolModel::from(&phrase),
-        editor:    MidiEditorModel::from(&phrase),
+        editor:    MidiEditor::from(&phrase),
         player:    MidiPlayer::from((&clock, &phrase)),
         size:      Measure::new(),
         midi_buf:  vec![vec![];65536],
diff --git a/src/status/status_edit.rs b/src/status/status_edit.rs
index 2bbde7be..5ea8de03 100644
--- a/src/status/status_edit.rs
+++ b/src/status/status_edit.rs
@@ -1,6 +1,6 @@
 use crate::*;
 
-pub struct MidiEditStatus<'a>(pub &'a MidiEditorModel);
+pub struct MidiEditStatus<'a>(pub &'a MidiEditor);
 render!(<Tui>|self:MidiEditStatus<'a>|{
 
     let (color, name, length, looped) = if let Some(phrase) = self.0.phrase().as_ref().map(|p|p.read().unwrap()) {
diff --git a/src/test.rs b/src/test.rs
index 5f7dcb0e..34c6e4aa 100644
--- a/src/test.rs
+++ b/src/test.rs
@@ -1,3 +1,52 @@
+//#[cfg(test)] mod test_focus {
+    //use super::focus::*;
+    //#[test] fn test_focus () {
+
+        //struct FocusTest {
+            //focused: char,
+            //cursor: (usize, usize)
+        //}
+
+        //impl HasFocus for FocusTest {
+            //type Item = char;
+            //fn focused (&self) -> Self::Item {
+                //self.focused
+            //}
+            //fn set_focused (&mut self, to: Self::Item) {
+                //self.focused = to
+            //}
+        //}
+
+        //impl FocusGrid for FocusTest {
+            //fn focus_cursor (&self) -> (usize, usize) {
+                //self.cursor
+            //}
+            //fn focus_cursor_mut (&mut self) -> &mut (usize, usize) {
+                //&mut self.cursor
+            //}
+            //fn focus_layout (&self) -> &[&[Self::Item]] {
+                //&[
+                    //&['a', 'a', 'a', 'b', 'b', 'd'],
+                    //&['a', 'a', 'a', 'b', 'b', 'd'],
+                    //&['a', 'a', 'a', 'c', 'c', 'd'],
+                    //&['a', 'a', 'a', 'c', 'c', 'd'],
+                    //&['e', 'e', 'e', 'e', 'e', 'e'],
+                //]
+            //}
+        //}
+
+        //let mut tester = FocusTest { focused: 'a', cursor: (0, 0) };
+
+        //tester.focus_right();
+        //assert_eq!(tester.cursor.0, 3);
+        //assert_eq!(tester.focused, 'b');
+
+        //tester.focus_down();
+        //assert_eq!(tester.cursor.1, 2);
+        //assert_eq!(tester.focused, 'c');
+
+    //}
+//}
 //use crate::*;
 
 //struct TestEngine([u16;4], Vec<Vec<char>>);
diff --git a/src/tui.rs b/src/tui.rs
index 8cd25285..361c45b4 100644
--- a/src/tui.rs
+++ b/src/tui.rs
@@ -1,27 +1,17 @@
 use crate::*;
 
-mod tui_input;  pub(crate) use self::tui_input::*;
-mod tui_output; pub(crate) use self::tui_output::*;
-
+mod tui_input; pub(crate) use self::tui_input::*;
 pub use self::tui_input::TuiInput;
+
+mod tui_output; pub(crate) use self::tui_output::*;
 pub use self::tui_output::TuiOutput;
 
-////////////////////////////////////////////////////////
-
 mod tui_style;
+
 mod tui_theme;  pub(crate) use self::tui_theme::*;
+
 mod tui_border; pub(crate) use self::tui_border::*;
 
-///////////////////////////////////////////////////////
-
-pub mod file_browser; pub(crate) use self::file_browser::*;
-
-////////////////////////////////////////////////////////
-
-pub fn render <F: Fn(&mut TuiOutput)->Usually<()>+Send+Sync> (render: F) -> impl Render<Tui> {
-    Widget::new(|_|Ok(Some([0u16,0u16])), render)
-}
-
 ////////////////////////////////////////////////////////
 
 pub struct Tui {
@@ -31,7 +21,7 @@ pub struct Tui {
     pub area:    [u16;4], // FIXME auto resize
 }
 
-impl crate::core::Engine for Tui {
+impl Engine for Tui {
     type Unit    = u16;
     type Size    = [Self::Unit;2];
     type Area    = [Self::Unit;4];
diff --git a/src/tui/tui_input.rs b/src/tui/tui_input.rs
index cabf317b..d8b20059 100644
--- a/src/tui/tui_input.rs
+++ b/src/tui/tui_input.rs
@@ -59,39 +59,6 @@ impl Input<Tui> for TuiInput {
     };
 }
 
-pub struct EventMap<'a, const N: usize, E, T, U>(
-    pub [(E, &'a dyn Fn(T) -> U); N],
-    pub Option<&'a dyn Fn(T) -> U>,
-);
-
-impl<'a, const N: usize, E: PartialEq, T, U> EventMap<'a, N, E, T, U> {
-    pub fn handle (&self, context: T, event: &E) -> Option<U> {
-        for (binding, handler) in self.0.iter() {
-            if event == binding {
-                return Some(handler(context))
-            }
-        }
-        return None
-    }
-}
-
-#[macro_export] macro_rules! event_map {
-    ($events:expr) => {
-        EventMap($events, None)
-    };
-    ($events:expr, $default: expr) => {
-        EventMap($events, $default)
-    };
-}
-
-#[macro_export] macro_rules! event_map_input_to_command {
-    ($Engine:ty: $Model:ty: $Command:ty: $EventMap:expr) => {
-        input_to_command!($Command: <$Engine>|state: $Model, input|{
-            event_map!($EventMap).handle(state, input.event())?
-        });
-    }
-}
-
 pub(crate) type KeyMapping<const N: usize, T> = [(TuiEvent, &'static dyn Fn(&T)->PhraseCommand);N];
 
 #[macro_export] macro_rules! kexp {
diff --git a/src/tui/tui_output.rs b/src/tui/tui_output.rs
index b346b535..b139c490 100644
--- a/src/tui/tui_output.rs
+++ b/src/tui/tui_output.rs
@@ -121,15 +121,6 @@ pub fn half_block (lower: bool, upper: bool) -> Option<char> {
     }
 }
 
-impl Render<Tui> for () {
-    fn min_size (&self, _: [u16;2]) -> Perhaps<[u16;2]> {
-        Ok(None)
-    }
-    fn render (&self, to: &mut TuiOutput) -> Usually<()> {
-        Ok(())
-    }
-}
-
 impl Render<Tui> for &str {
     fn min_size (&self, _: [u16;2]) -> Perhaps<[u16;2]> {
         // TODO: line breaks