diff --git a/Cargo.lock b/Cargo.lock
index a5d8ba38..a07b0cb5 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1540,6 +1540,7 @@ dependencies = [
  "symphonia",
  "tek_engine",
  "tengri",
+ "uuid",
  "wavers",
 ]
 
diff --git a/crates/engine/src/clock.rs b/crates/app/src/clock.rs
similarity index 100%
rename from crates/engine/src/clock.rs
rename to crates/app/src/clock.rs
diff --git a/crates/engine/src/clock/clock_api.rs b/crates/app/src/clock/clock_api.rs
similarity index 100%
rename from crates/engine/src/clock/clock_api.rs
rename to crates/app/src/clock/clock_api.rs
diff --git a/crates/engine/src/clock/clock_model.rs b/crates/app/src/clock/clock_model.rs
similarity index 100%
rename from crates/engine/src/clock/clock_model.rs
rename to crates/app/src/clock/clock_model.rs
diff --git a/crates/app/src/editor.rs b/crates/app/src/editor.rs
new file mode 100644
index 00000000..62c7b812
--- /dev/null
+++ b/crates/app/src/editor.rs
@@ -0,0 +1,3 @@
+mod editor_api;
+mod editor_model;
+mod editor_view;
diff --git a/crates/app/src/editor/editor_api.rs b/crates/app/src/editor/editor_api.rs
new file mode 100644
index 00000000..1ac85118
--- /dev/null
+++ b/crates/app/src/editor/editor_api.rs
@@ -0,0 +1,97 @@
+use crate::*;
+
+provide!(bool: |self: MidiEditor| {
+    ":true" => true,
+    ":false" => false,
+    ":time-lock" => self.time_lock().get(),
+    ":time-lock-toggle" => !self.time_lock().get(),
+});
+
+provide!(usize: |self: MidiEditor| {
+    ":note-length" => self.note_len(),
+
+    ":note-pos"      => self.note_pos(),
+    ":note-pos-next" => self.note_pos() + 1,
+    ":note-pos-prev" => self.note_pos().saturating_sub(1),
+    ":note-pos-next-octave" => self.note_pos() + 12,
+    ":note-pos-prev-octave" => self.note_pos().saturating_sub(12),
+
+    ":note-len"      => self.note_len(),
+    ":note-len-next" => self.note_len() + 1,
+    ":note-len-prev" => self.note_len().saturating_sub(1),
+
+    ":note-range"      => self.note_axis().get(),
+    ":note-range-prev" => self.note_axis().get() + 1,
+    ":note-range-next" => self.note_axis().get().saturating_sub(1),
+
+    ":time-pos"      => self.time_pos(),
+    ":time-pos-next" => self.time_pos() + self.time_zoom().get(),
+    ":time-pos-prev" => self.time_pos().saturating_sub(self.time_zoom().get()),
+
+    ":time-zoom"      => self.time_zoom().get(),
+    ":time-zoom-next" => self.time_zoom().get() + 1,
+    ":time-zoom-prev" => self.time_zoom().get().saturating_sub(1).max(1),
+});
+
+atom_command!(MidiEditCommand: |state: MidiEditor| {
+    ("note/append" []         Some(Self::AppendNote))
+    ("note/put"    []         Some(Self::PutNote))
+    ("note/del"    []         Some(Self::DelNote))
+    ("note/pos"    [a: usize] Some(Self::SetNoteCursor(a.expect("no note cursor"))))
+    ("note/len"    [a: usize] Some(Self::SetNoteLength(a.expect("no note length"))))
+    ("time/pos"    [a: usize] Some(Self::SetTimeCursor(a.expect("no time cursor"))))
+    ("time/zoom"   [a: usize] Some(Self::SetTimeZoom(a.expect("no time zoom"))))
+    ("time/lock"   [a: bool]  Some(Self::SetTimeLock(a.expect("no time lock"))))
+    ("time/lock"   []         Some(Self::SetTimeLock(!state.time_lock().get())))
+});
+
+#[derive(Clone, Debug)] pub enum MidiEditCommand {
+    // TODO: 1-9 seek markers that by default start every 8th of the clip
+    AppendNote,
+    PutNote,
+    DelNote,
+    SetNoteCursor(usize),
+    SetNoteLength(usize),
+    SetNoteScroll(usize),
+    SetTimeCursor(usize),
+    SetTimeScroll(usize),
+    SetTimeZoom(usize),
+    SetTimeLock(bool),
+    Show(Option<Arc<RwLock<MidiClip>>>),
+}
+
+handle!(TuiIn: |self: MidiEditor, input|Ok(if let Some(command) = self.keys.command(self, input) {
+    command.execute(self)?;
+    Some(true)
+} else {
+    None
+}));
+
+impl Command<MidiEditor> for MidiEditCommand {
+    fn execute (self, state: &mut MidiEditor) -> Perhaps<Self> {
+        use MidiEditCommand::*;
+        match self {
+            Show(clip) => { state.set_clip(clip.as_ref()); },
+            DelNote    => {},
+            PutNote    => { state.put_note(false); },
+            AppendNote => { state.put_note(true); },
+            SetTimeZoom(x) => { state.time_zoom().set(x); state.redraw(); },
+            SetTimeLock(x) => { state.time_lock().set(x); },
+            SetTimeScroll(x) => { state.time_start().set(x); },
+            SetNoteScroll(x) => { state.note_lo().set(x.min(127)); },
+            SetNoteLength(x) => {
+                let note_len = state.note_len();
+                let time_zoom = state.time_zoom().get();
+                state.set_note_len(x);
+                //if note_len / time_zoom != x / time_zoom {
+                    state.redraw();
+                //}
+            },
+            SetTimeCursor(x) => { state.set_time_pos(x); },
+            SetNoteCursor(note) => { state.set_note_pos(note.min(127)); },
+            //_ => todo!("{:?}", self)
+        }
+        Ok(None)
+    }
+}
+
diff --git a/crates/engine/src/midi/clip/clip_editor.rs b/crates/app/src/editor/editor_model.rs
similarity index 59%
rename from crates/engine/src/midi/clip/clip_editor.rs
rename to crates/app/src/editor/editor_model.rs
index efdd92d6..befec6be 100644
--- a/crates/engine/src/midi/clip/clip_editor.rs
+++ b/crates/app/src/editor/editor_model.rs
@@ -51,39 +51,6 @@ from!(|clip: Option<Arc<RwLock<MidiClip>>>|MidiEditor = {
     model
 });
 
-provide!(bool: |self: MidiEditor| {
-    ":true" => true,
-    ":false" => false,
-    ":time-lock" => self.time_lock().get(),
-    ":time-lock-toggle" => !self.time_lock().get(),
-});
-
-provide!(usize: |self: MidiEditor| {
-    ":note-length" => self.note_len(),
-
-    ":note-pos"      => self.note_pos(),
-    ":note-pos-next" => self.note_pos() + 1,
-    ":note-pos-prev" => self.note_pos().saturating_sub(1),
-    ":note-pos-next-octave" => self.note_pos() + 12,
-    ":note-pos-prev-octave" => self.note_pos().saturating_sub(12),
-
-    ":note-len"      => self.note_len(),
-    ":note-len-next" => self.note_len() + 1,
-    ":note-len-prev" => self.note_len().saturating_sub(1),
-
-    ":note-range"      => self.note_axis().get(),
-    ":note-range-prev" => self.note_axis().get() + 1,
-    ":note-range-next" => self.note_axis().get().saturating_sub(1),
-
-    ":time-pos"      => self.time_pos(),
-    ":time-pos-next" => self.time_pos() + self.time_zoom().get(),
-    ":time-pos-prev" => self.time_pos().saturating_sub(self.time_zoom().get()),
-
-    ":time-zoom"      => self.time_zoom().get(),
-    ":time-zoom-next" => self.time_zoom().get() + 1,
-    ":time-zoom-prev" => self.time_zoom().get().saturating_sub(1).max(1),
-});
-
 impl MidiEditor {
 
     /// Put note at current position
@@ -181,64 +148,3 @@ impl MidiViewer for MidiEditor {
     fn set_clip (&mut self, p: Option<&Arc<RwLock<MidiClip>>>) { self.mode.set_clip(p) }
 }
 
-atom_command!(MidiEditCommand: |state: MidiEditor| {
-    ("note/append" []         Some(Self::AppendNote))
-    ("note/put"    []         Some(Self::PutNote))
-    ("note/del"    []         Some(Self::DelNote))
-    ("note/pos"    [a: usize] Some(Self::SetNoteCursor(a.expect("no note cursor"))))
-    ("note/len"    [a: usize] Some(Self::SetNoteLength(a.expect("no note length"))))
-    ("time/pos"    [a: usize] Some(Self::SetTimeCursor(a.expect("no time cursor"))))
-    ("time/zoom"   [a: usize] Some(Self::SetTimeZoom(a.expect("no time zoom"))))
-    ("time/lock"   [a: bool]  Some(Self::SetTimeLock(a.expect("no time lock"))))
-    ("time/lock"   []         Some(Self::SetTimeLock(!state.time_lock().get())))
-});
-
-#[derive(Clone, Debug)] pub enum MidiEditCommand {
-    // TODO: 1-9 seek markers that by default start every 8th of the clip
-    AppendNote,
-    PutNote,
-    DelNote,
-    SetNoteCursor(usize),
-    SetNoteLength(usize),
-    SetNoteScroll(usize),
-    SetTimeCursor(usize),
-    SetTimeScroll(usize),
-    SetTimeZoom(usize),
-    SetTimeLock(bool),
-    Show(Option<Arc<RwLock<MidiClip>>>),
-}
-
-handle!(TuiIn: |self: MidiEditor, input|Ok(if let Some(command) = self.keys.command(self, input) {
-    command.execute(self)?;
-    Some(true)
-} else {
-    None
-}));
-
-impl Command<MidiEditor> for MidiEditCommand {
-    fn execute (self, state: &mut MidiEditor) -> Perhaps<Self> {
-        use MidiEditCommand::*;
-        match self {
-            Show(clip) => { state.set_clip(clip.as_ref()); },
-            DelNote    => {},
-            PutNote    => { state.put_note(false); },
-            AppendNote => { state.put_note(true); },
-            SetTimeZoom(x) => { state.time_zoom().set(x); state.redraw(); },
-            SetTimeLock(x) => { state.time_lock().set(x); },
-            SetTimeScroll(x) => { state.time_start().set(x); },
-            SetNoteScroll(x) => { state.note_lo().set(x.min(127)); },
-            SetNoteLength(x) => {
-                let note_len = state.note_len();
-                let time_zoom = state.time_zoom().get();
-                state.set_note_len(x);
-                //if note_len / time_zoom != x / time_zoom {
-                    state.redraw();
-                //}
-            },
-            SetTimeCursor(x) => { state.set_time_pos(x); },
-            SetNoteCursor(note) => { state.set_note_pos(note.min(127)); },
-            //_ => todo!("{:?}", self)
-        }
-        Ok(None)
-    }
-}
diff --git a/crates/engine/src/midi/piano/piano_h.rs b/crates/app/src/editor/editor_view.rs
similarity index 92%
rename from crates/engine/src/midi/piano/piano_h.rs
rename to crates/app/src/editor/editor_view.rs
index d4650cf4..67c9dc18 100644
--- a/crates/engine/src/midi/piano/piano_h.rs
+++ b/crates/app/src/editor/editor_view.rs
@@ -325,3 +325,39 @@ fn to_key (note: usize) -> &'static str {
         _  => unreachable!(),
     }
 }
+
+pub struct OctaveVertical {
+    on:     [bool; 12],
+    colors: [Color; 3]
+}
+
+impl Default for OctaveVertical {
+    fn default () -> Self {
+        Self {
+            on:     [false; 12],
+            colors: [Rgb(255,255,255), Rgb(0,0,0), Rgb(255,0,0)]
+        }
+    }
+}
+
+impl OctaveVertical {
+    fn color (&self, pitch: usize) -> Color {
+        let pitch = pitch % 12;
+        self.colors[if self.on[pitch] { 2 } else {
+            match pitch { 0 | 2 | 4 | 5 | 6 | 8 | 10 => 0, _ => 1 }
+        }]
+    }
+}
+
+impl Content<TuiOut> for OctaveVertical {
+    fn content (&self) -> impl Render<TuiOut> {
+        row!(
+            Tui::fg_bg(self.color(0),  self.color(1),  "▙"),
+            Tui::fg_bg(self.color(2),  self.color(3),  "▙"),
+            Tui::fg_bg(self.color(4),  self.color(5),  "▌"),
+            Tui::fg_bg(self.color(6),  self.color(7),  "▟"),
+            Tui::fg_bg(self.color(8),  self.color(9),  "▟"),
+            Tui::fg_bg(self.color(10), self.color(11), "▟"),
+        )
+    }
+}
diff --git a/crates/app/src/lib.rs b/crates/app/src/lib.rs
index 27b509c2..4ff7b835 100644
--- a/crates/app/src/lib.rs
+++ b/crates/app/src/lib.rs
@@ -41,6 +41,9 @@ mod audio;  pub use self::audio::*;
 mod model;  pub use self::model::*;
 mod view;   pub use self::view::*;
 
+mod pool;
+mod editor;
+
 #[cfg(test)] #[test] fn test_model () {
     let mut tek = Tek::default();
     let _ = tek.clip();
diff --git a/crates/app/src/model.rs b/crates/app/src/model.rs
index 0ed65783..ab1e0fb9 100644
--- a/crates/app/src/model.rs
+++ b/crates/app/src/model.rs
@@ -787,11 +787,3 @@ impl HasTracks for Tek {
     fn tracks (&self) -> &Vec<Track> { &self.tracks }
     fn tracks_mut (&mut self) -> &mut Vec<Track> { &mut self.tracks }
 }
-
-#[derive(Debug)]
-pub enum Device {
-    Sequencer(MidiPlayer),
-    Sampler(Sampler),
-    #[cfg(feature="host")]
-    Plugin(Plugin),
-}
diff --git a/crates/engine/src/midi/pool.rs b/crates/app/src/pool.rs
similarity index 100%
rename from crates/engine/src/midi/pool.rs
rename to crates/app/src/pool.rs
diff --git a/crates/engine/src/midi/pool/pool_api.rs b/crates/app/src/pool/pool_api.rs
similarity index 100%
rename from crates/engine/src/midi/pool/pool_api.rs
rename to crates/app/src/pool/pool_api.rs
diff --git a/crates/engine/src/midi/pool/pool_clips.rs b/crates/app/src/pool/pool_clips.rs
similarity index 100%
rename from crates/engine/src/midi/pool/pool_clips.rs
rename to crates/app/src/pool/pool_clips.rs
diff --git a/crates/engine/src/midi/mode.rs b/crates/app/src/pool/pool_mode.rs
similarity index 99%
rename from crates/engine/src/midi/mode.rs
rename to crates/app/src/pool/pool_mode.rs
index 6fd9c01c..0b3bd49f 100644
--- a/crates/engine/src/midi/mode.rs
+++ b/crates/app/src/pool/pool_mode.rs
@@ -16,3 +16,4 @@ pub enum PoolMode {
     /// Save clip to disk
     Export(usize, FileBrowser),
 }
+
diff --git a/crates/engine/src/midi/mode/mode_browse.rs b/crates/app/src/pool/pool_mode/mode_browse.rs
similarity index 100%
rename from crates/engine/src/midi/mode/mode_browse.rs
rename to crates/app/src/pool/pool_mode/mode_browse.rs
diff --git a/crates/engine/src/midi/mode/mode_length.rs b/crates/app/src/pool/pool_mode/mode_length.rs
similarity index 100%
rename from crates/engine/src/midi/mode/mode_length.rs
rename to crates/app/src/pool/pool_mode/mode_length.rs
diff --git a/crates/engine/src/midi/mode/mode_rename.rs b/crates/app/src/pool/pool_mode/mode_rename.rs
similarity index 100%
rename from crates/engine/src/midi/mode/mode_rename.rs
rename to crates/app/src/pool/pool_mode/mode_rename.rs
diff --git a/crates/engine/src/midi/pool/pool_model.rs b/crates/app/src/pool/pool_model.rs
similarity index 100%
rename from crates/engine/src/midi/pool/pool_model.rs
rename to crates/app/src/pool/pool_model.rs
diff --git a/crates/engine/src/midi/pool/pool_view.rs b/crates/app/src/pool/pool_view.rs
similarity index 100%
rename from crates/engine/src/midi/pool/pool_view.rs
rename to crates/app/src/pool/pool_view.rs
diff --git a/crates/device/Cargo.toml b/crates/device/Cargo.toml
index 9f94bfbb..ce041180 100644
--- a/crates/device/Cargo.toml
+++ b/crates/device/Cargo.toml
@@ -6,6 +6,7 @@ version = { workspace = true }
 [dependencies]
 tengri     = { workspace = true }
 tek_engine = { workspace = true }
+uuid       = { workspace = true, optional = true }
 livi       = { workspace = true, optional = true }
 symphonia  = { workspace = true, optional = true }
 wavers     = { workspace = true, optional = true }
@@ -14,4 +15,4 @@ wavers     = { workspace = true, optional = true }
 default   = [ "sequencer", "sampler" ]
 lv2       = [ "livi" ]
 sampler   = [ "symphonia", "wavers" ]
-sequencer = []
+sequencer = [ "uuid" ]
diff --git a/crates/device/src/lib.rs b/crates/device/src/lib.rs
index e69de29b..4bae13d6 100644
--- a/crates/device/src/lib.rs
+++ b/crates/device/src/lib.rs
@@ -0,0 +1,35 @@
+#![feature(let_chains)]
+
+pub(crate) use std::cmp::Ord;
+pub(crate) use std::fmt::{Debug, Formatter};
+pub(crate) use std::thread::JoinHandle;
+pub(crate) use std::sync::{Arc, RwLock, atomic::{AtomicUsize, Ordering::Relaxed}};
+pub(crate) use std::fs::File;
+pub(crate) use std::path::PathBuf;
+pub(crate) use std::error::Error;
+pub(crate) use std::ffi::OsString;
+
+pub(crate) use ::tengri::{dsl::*, input::*, output::*, tui::{*, ratatui::prelude::*}};
+pub(crate) use ::tek_engine::*;
+pub(crate) use ::tek_engine::midi::{u7, LiveEvent, MidiMessage};
+pub(crate) use ::tek_engine::jack::{Control, ProcessScope, MidiWriter, RawMidi};
+pub(crate) use ratatui::{prelude::Rect, widgets::{Widget, canvas::{Canvas, Line}}};
+
+#[cfg(feature = "sequencer")] mod sequencer;
+#[cfg(feature = "sequencer")] pub use self::sequencer::*;
+
+#[cfg(feature = "sampler")] mod sampler;
+#[cfg(feature = "sampler")] pub use self::sampler::*;
+
+#[cfg(feature = "plugin")] mod plugin;
+#[cfg(feature = "plugin")] pub use self::plugin::*;
+
+#[derive(Debug)]
+pub enum Device {
+    #[cfg(feature = "sequencer")]
+    Sequencer(MidiPlayer),
+    #[cfg(feature = "sampler")]
+    Sampler(Sampler),
+    #[cfg(feature = "plugin")]
+    Plugin(Plugin),
+}
diff --git a/crates/device/src/plugin.rs b/crates/device/src/plugin.rs
index 40825854..f3f47d79 100644
--- a/crates/device/src/plugin.rs
+++ b/crates/device/src/plugin.rs
@@ -1,8 +1,281 @@
-mod plugin; pub use self::plugin::*;
-mod lv2;    pub use self::lv2::*;
-pub(crate) use std::cmp::Ord;
-pub(crate) use std::fmt::{Debug, Formatter};
-pub(crate) use std::sync::{Arc, RwLock};
-pub(crate) use std::thread::JoinHandle;
-pub(crate) use ::tek_jack::{*, jack::*};
-pub(crate) use ::tengri::{output::*, tui::{*, ratatui::prelude::*}};
+use crate::*;
+
+mod lv2;
+mod lv2_gui;
+mod lv2_tui;
+mod vst2_tui;
+mod vst3_tui;
+
+/// A plugin device.
+#[derive(Debug)]
+pub struct Plugin {
+    /// JACK client handle (needs to not be dropped for standalone mode to work).
+    pub jack:       Jack,
+    pub name:       Arc<str>,
+    pub path:       Option<Arc<str>>,
+    pub plugin:     Option<PluginKind>,
+    pub selected:   usize,
+    pub mapping:    bool,
+    pub midi_ins:   Vec<Port<MidiIn>>,
+    pub midi_outs:  Vec<Port<MidiOut>>,
+    pub audio_ins:  Vec<Port<AudioIn>>,
+    pub audio_outs: Vec<Port<AudioOut>>,
+}
+
+/// Supported plugin formats.
+#[derive(Default)]
+pub enum PluginKind {
+    #[default] None,
+    LV2(LV2Plugin),
+    VST2 { instance: () /*::vst::host::PluginInstance*/ },
+    VST3,
+}
+
+impl Debug for PluginKind {
+    fn fmt (&self, f: &mut Formatter<'_>) -> std::result::Result<(), std::fmt::Error> {
+        write!(f, "{}", match self {
+            Self::None     => "(none)",
+            Self::LV2(_)   => "LV2",
+            Self::VST2{..} => "VST2",
+            Self::VST3     => "VST3",
+        })
+    }
+}
+impl Plugin {
+    pub fn new_lv2 (
+        jack: &Jack,
+        name: &str,
+        path: &str,
+    ) -> Usually<Self> {
+        Ok(Self {
+            jack:       jack.clone(),
+            name:       name.into(),
+            path:       Some(String::from(path).into()),
+            plugin:     Some(PluginKind::LV2(LV2Plugin::new(path)?)),
+            selected:   0,
+            mapping:    false,
+            midi_ins:   vec![],
+            midi_outs:  vec![],
+            audio_ins:  vec![],
+            audio_outs: vec![],
+        })
+    }
+}
+
+pub struct PluginAudio(Arc<RwLock<Plugin>>);
+from!(|model: &Arc<RwLock<Plugin>>| PluginAudio = Self(model.clone()));
+audio!(|self: PluginAudio, _client, scope|{
+    let state = &mut*self.0.write().unwrap();
+    match state.plugin.as_mut() {
+        Some(PluginKind::LV2(LV2Plugin {
+            features,
+            ref mut instance,
+            ref mut input_buffer,
+            ..
+        })) => {
+            let urid = features.midi_urid();
+            input_buffer.clear();
+            for port in state.midi_ins.iter() {
+                let mut atom = ::livi::event::LV2AtomSequence::new(
+                    &features,
+                    scope.n_frames() as usize
+                );
+                for event in port.iter(scope) {
+                    match event.bytes.len() {
+                        3 => atom.push_midi_event::<3>(
+                            event.time as i64,
+                            urid,
+                            &event.bytes[0..3]
+                        ).unwrap(),
+                        _ => {}
+                    }
+                }
+                input_buffer.push(atom);
+            }
+            let mut outputs = vec![];
+            for _ in state.midi_outs.iter() {
+                outputs.push(::livi::event::LV2AtomSequence::new(
+                    features,
+                    scope.n_frames() as usize
+                ));
+            }
+            let ports = ::livi::EmptyPortConnections::new()
+                .with_atom_sequence_inputs(input_buffer.iter())
+                .with_atom_sequence_outputs(outputs.iter_mut())
+                .with_audio_inputs(state.audio_ins.iter().map(|o|o.as_slice(scope)))
+                .with_audio_outputs(state.audio_outs.iter_mut().map(|o|o.as_mut_slice(scope)));
+            unsafe {
+                instance.run(scope.n_frames() as usize, ports).unwrap()
+            };
+        },
+        _ => todo!("only lv2 is supported")
+    }
+    Control::Continue
+});
+
+    //fn jack_from_lv2 (name: &str, plugin: &::livi::Plugin) -> Usually<Jack> {
+        //let counts = plugin.port_counts();
+        //let mut jack = Jack::new(name)?;
+        //for i in 0..counts.atom_sequence_inputs {
+            //jack = jack.midi_in(&format!("midi-in-{i}"))
+        //}
+        //for i in 0..counts.atom_sequence_outputs {
+            //jack = jack.midi_out(&format!("midi-out-{i}"));
+        //}
+        //for i in 0..counts.audio_inputs {
+            //jack = jack.audio_in(&format!("audio-in-{i}"));
+        //}
+        //for i in 0..counts.audio_outputs {
+            //jack = jack.audio_out(&format!("audio-out-{i}"));
+        //}
+        //Ok(jack)
+    //}
+
+impl Plugin {
+    /// Create a plugin host device.
+    pub fn new (
+        jack: &Jack,
+        name: &str,
+    ) -> Usually<Self> {
+        Ok(Self {
+            //_engine:    Default::default(),
+            jack:       jack.clone(),
+            name:       name.into(),
+            path:       None,
+            plugin:     None,
+            selected:   0,
+            mapping:    false,
+            audio_ins:  vec![],
+            audio_outs: vec![],
+            midi_ins:   vec![],
+            midi_outs:  vec![],
+            //ports:      JackPorts::default()
+        })
+    }
+}
+impl Content<TuiOut> for Plugin {
+    fn render (&self, to: &mut TuiOut) {
+        let area = to.area();
+        let [x, y, _, height] = area;
+        let mut width = 20u16;
+        match &self.plugin {
+            Some(PluginKind::LV2(LV2Plugin { port_list, instance, .. })) => {
+                let start = self.selected.saturating_sub((height as usize / 2).saturating_sub(1));
+                let end   = start + height as usize - 2;
+                //draw_box(buf, Rect { x, y, width, height });
+                for i in start..end {
+                    if let Some(port) = port_list.get(i) {
+                        let value = if let Some(value) = instance.control_input(port.index) {
+                            value
+                        } else {
+                            port.default_value
+                        };
+                        //let label = &format!("C·· M·· {:25} = {value:.03}", port.name);
+                        let label = &format!("{:25} = {value:.03}", port.name);
+                        width = width.max(label.len() as u16 + 4);
+                        let style = if i == self.selected {
+                            Some(Style::default().green())
+                        } else {
+                            None
+                        } ;
+                        to.blit(&label, x + 2, y + 1 + i as u16 - start as u16, style);
+                    } else {
+                        break
+                    }
+                }
+            },
+            _ => {}
+        };
+        draw_header(self, to, x, y, width);
+    }
+}
+
+fn draw_header (state: &Plugin, to: &mut TuiOut, x: u16, y: u16, w: u16) {
+    let style  = Style::default().gray();
+    let label1 = format!(" {}", state.name);
+    to.blit(&label1, x + 1, y, Some(style.white().bold()));
+    if let Some(ref path) = state.path {
+        let label2 = format!("{}…", &path[..((w as usize - 10).min(path.len()))]);
+        to.blit(&label2, x + 2 + label1.len() as u16, y, Some(style.not_dim()));
+    }
+    //Ok(Rect { x, y, width: w, height: 1 })
+}
+
+//handle!(TuiIn: |self:Plugin, from|{
+    //match from.event() {
+        //kpat!(KeyCode::Up) => {
+            //self.selected = self.selected.saturating_sub(1);
+            //Ok(Some(true))
+        //},
+        //kpat!(KeyCode::Down) => {
+            //self.selected = (self.selected + 1).min(match &self.plugin {
+                //Some(PluginKind::LV2(LV2Plugin { port_list, .. })) => port_list.len() - 1,
+                //_ => unimplemented!()
+            //});
+            //Ok(Some(true))
+        //},
+        //kpat!(KeyCode::PageUp) => {
+            //self.selected = self.selected.saturating_sub(8);
+            //Ok(Some(true))
+        //},
+        //kpat!(KeyCode::PageDown) => {
+            //self.selected = (self.selected + 10).min(match &self.plugin {
+                //Some(PluginKind::LV2(LV2Plugin { port_list, .. })) => port_list.len() - 1,
+                //_ => unimplemented!()
+            //});
+            //Ok(Some(true))
+        //},
+        //kpat!(KeyCode::Char(',')) => {
+            //match self.plugin.as_mut() {
+                //Some(PluginKind::LV2(LV2Plugin { port_list, ref mut instance, .. })) => {
+                    //let index = port_list[self.selected].index;
+                    //if let Some(value) = instance.control_input(index) {
+                        //instance.set_control_input(index, value - 0.01);
+                    //}
+                //},
+                //_ => {}
+            //}
+            //Ok(Some(true))
+        //},
+        //kpat!(KeyCode::Char('.')) => {
+            //match self.plugin.as_mut() {
+                //Some(PluginKind::LV2(LV2Plugin { port_list, ref mut instance, .. })) => {
+                    //let index = port_list[self.selected].index;
+                    //if let Some(value) = instance.control_input(index) {
+                        //instance.set_control_input(index, value + 0.01);
+                    //}
+                //},
+                //_ => {}
+            //}
+            //Ok(Some(true))
+        //},
+        //kpat!(KeyCode::Char('g')) => {
+            //match self.plugin {
+                ////Some(PluginKind::LV2(ref mut plugin)) => {
+                    ////plugin.ui_thread = Some(run_lv2_ui(LV2PluginUI::new()?)?);
+                ////},
+                //Some(_) => unreachable!(),
+                //None => {}
+            //}
+            //Ok(Some(true))
+        //},
+        //_ => Ok(None)
+    //}
+//});
+
+//from_atom!("plugin/lv2" => |jack: &Jack, args| -> Plugin {
+    //let mut name = String::new();
+    //let mut path = String::new();
+    //atom!(atom in args {
+        //Atom::Map(map) => {
+            //if let Some(Atom::Str(n)) = map.get(&Atom::Key(":name")) {
+                //name = String::from(*n);
+            //}
+            //if let Some(Atom::Str(p)) = map.get(&Atom::Key(":path")) {
+                //path = String::from(*p);
+            //}
+        //},
+        //_ => panic!("unexpected in lv2 '{name}'"),
+    //});
+    //Plugin::new_lv2(jack, &name, &path)
+//});
diff --git a/crates/device/src/plugin/plugin.rs b/crates/device/src/plugin/plugin.rs
deleted file mode 100644
index ddd58e65..00000000
--- a/crates/device/src/plugin/plugin.rs
+++ /dev/null
@@ -1,275 +0,0 @@
-use crate::*;
-
-/// A plugin device.
-#[derive(Debug)]
-pub struct Plugin {
-    /// JACK client handle (needs to not be dropped for standalone mode to work).
-    pub jack:       Jack,
-    pub name:       Arc<str>,
-    pub path:       Option<Arc<str>>,
-    pub plugin:     Option<PluginKind>,
-    pub selected:   usize,
-    pub mapping:    bool,
-    pub midi_ins:   Vec<Port<MidiIn>>,
-    pub midi_outs:  Vec<Port<MidiOut>>,
-    pub audio_ins:  Vec<Port<AudioIn>>,
-    pub audio_outs: Vec<Port<AudioOut>>,
-}
-
-/// Supported plugin formats.
-#[derive(Default)]
-pub enum PluginKind {
-    #[default] None,
-    LV2(LV2Plugin),
-    VST2 { instance: () /*::vst::host::PluginInstance*/ },
-    VST3,
-}
-
-impl Debug for PluginKind {
-    fn fmt (&self, f: &mut Formatter<'_>) -> std::result::Result<(), std::fmt::Error> {
-        write!(f, "{}", match self {
-            Self::None     => "(none)",
-            Self::LV2(_)   => "LV2",
-            Self::VST2{..} => "VST2",
-            Self::VST3     => "VST3",
-        })
-    }
-}
-impl Plugin {
-    pub fn new_lv2 (
-        jack: &Jack,
-        name: &str,
-        path: &str,
-    ) -> Usually<Self> {
-        Ok(Self {
-            jack:       jack.clone(),
-            name:       name.into(),
-            path:       Some(String::from(path).into()),
-            plugin:     Some(PluginKind::LV2(LV2Plugin::new(path)?)),
-            selected:   0,
-            mapping:    false,
-            midi_ins:   vec![],
-            midi_outs:  vec![],
-            audio_ins:  vec![],
-            audio_outs: vec![],
-        })
-    }
-}
-
-pub struct PluginAudio(Arc<RwLock<Plugin>>);
-from!(|model: &Arc<RwLock<Plugin>>| PluginAudio = Self(model.clone()));
-audio!(|self: PluginAudio, _client, scope|{
-    let state = &mut*self.0.write().unwrap();
-    match state.plugin.as_mut() {
-        Some(PluginKind::LV2(LV2Plugin {
-            features,
-            ref mut instance,
-            ref mut input_buffer,
-            ..
-        })) => {
-            let urid = features.midi_urid();
-            input_buffer.clear();
-            for port in state.midi_ins.iter() {
-                let mut atom = ::livi::event::LV2AtomSequence::new(
-                    &features,
-                    scope.n_frames() as usize
-                );
-                for event in port.iter(scope) {
-                    match event.bytes.len() {
-                        3 => atom.push_midi_event::<3>(
-                            event.time as i64,
-                            urid,
-                            &event.bytes[0..3]
-                        ).unwrap(),
-                        _ => {}
-                    }
-                }
-                input_buffer.push(atom);
-            }
-            let mut outputs = vec![];
-            for _ in state.midi_outs.iter() {
-                outputs.push(::livi::event::LV2AtomSequence::new(
-                    features,
-                    scope.n_frames() as usize
-                ));
-            }
-            let ports = ::livi::EmptyPortConnections::new()
-                .with_atom_sequence_inputs(input_buffer.iter())
-                .with_atom_sequence_outputs(outputs.iter_mut())
-                .with_audio_inputs(state.audio_ins.iter().map(|o|o.as_slice(scope)))
-                .with_audio_outputs(state.audio_outs.iter_mut().map(|o|o.as_mut_slice(scope)));
-            unsafe {
-                instance.run(scope.n_frames() as usize, ports).unwrap()
-            };
-        },
-        _ => todo!("only lv2 is supported")
-    }
-    Control::Continue
-});
-
-    //fn jack_from_lv2 (name: &str, plugin: &::livi::Plugin) -> Usually<Jack> {
-        //let counts = plugin.port_counts();
-        //let mut jack = Jack::new(name)?;
-        //for i in 0..counts.atom_sequence_inputs {
-            //jack = jack.midi_in(&format!("midi-in-{i}"))
-        //}
-        //for i in 0..counts.atom_sequence_outputs {
-            //jack = jack.midi_out(&format!("midi-out-{i}"));
-        //}
-        //for i in 0..counts.audio_inputs {
-            //jack = jack.audio_in(&format!("audio-in-{i}"));
-        //}
-        //for i in 0..counts.audio_outputs {
-            //jack = jack.audio_out(&format!("audio-out-{i}"));
-        //}
-        //Ok(jack)
-    //}
-
-impl Plugin {
-    /// Create a plugin host device.
-    pub fn new (
-        jack: &Jack,
-        name: &str,
-    ) -> Usually<Self> {
-        Ok(Self {
-            //_engine:    Default::default(),
-            jack:       jack.clone(),
-            name:       name.into(),
-            path:       None,
-            plugin:     None,
-            selected:   0,
-            mapping:    false,
-            audio_ins:  vec![],
-            audio_outs: vec![],
-            midi_ins:   vec![],
-            midi_outs:  vec![],
-            //ports:      JackPorts::default()
-        })
-    }
-}
-impl Content<TuiOut> for Plugin {
-    fn render (&self, to: &mut TuiOut) {
-        let area = to.area();
-        let [x, y, _, height] = area;
-        let mut width = 20u16;
-        match &self.plugin {
-            Some(PluginKind::LV2(LV2Plugin { port_list, instance, .. })) => {
-                let start = self.selected.saturating_sub((height as usize / 2).saturating_sub(1));
-                let end   = start + height as usize - 2;
-                //draw_box(buf, Rect { x, y, width, height });
-                for i in start..end {
-                    if let Some(port) = port_list.get(i) {
-                        let value = if let Some(value) = instance.control_input(port.index) {
-                            value
-                        } else {
-                            port.default_value
-                        };
-                        //let label = &format!("C·· M·· {:25} = {value:.03}", port.name);
-                        let label = &format!("{:25} = {value:.03}", port.name);
-                        width = width.max(label.len() as u16 + 4);
-                        let style = if i == self.selected {
-                            Some(Style::default().green())
-                        } else {
-                            None
-                        } ;
-                        to.blit(&label, x + 2, y + 1 + i as u16 - start as u16, style);
-                    } else {
-                        break
-                    }
-                }
-            },
-            _ => {}
-        };
-        draw_header(self, to, x, y, width);
-    }
-}
-
-fn draw_header (state: &Plugin, to: &mut TuiOut, x: u16, y: u16, w: u16) {
-    let style  = Style::default().gray();
-    let label1 = format!(" {}", state.name);
-    to.blit(&label1, x + 1, y, Some(style.white().bold()));
-    if let Some(ref path) = state.path {
-        let label2 = format!("{}…", &path[..((w as usize - 10).min(path.len()))]);
-        to.blit(&label2, x + 2 + label1.len() as u16, y, Some(style.not_dim()));
-    }
-    //Ok(Rect { x, y, width: w, height: 1 })
-}
-
-//handle!(TuiIn: |self:Plugin, from|{
-    //match from.event() {
-        //kpat!(KeyCode::Up) => {
-            //self.selected = self.selected.saturating_sub(1);
-            //Ok(Some(true))
-        //},
-        //kpat!(KeyCode::Down) => {
-            //self.selected = (self.selected + 1).min(match &self.plugin {
-                //Some(PluginKind::LV2(LV2Plugin { port_list, .. })) => port_list.len() - 1,
-                //_ => unimplemented!()
-            //});
-            //Ok(Some(true))
-        //},
-        //kpat!(KeyCode::PageUp) => {
-            //self.selected = self.selected.saturating_sub(8);
-            //Ok(Some(true))
-        //},
-        //kpat!(KeyCode::PageDown) => {
-            //self.selected = (self.selected + 10).min(match &self.plugin {
-                //Some(PluginKind::LV2(LV2Plugin { port_list, .. })) => port_list.len() - 1,
-                //_ => unimplemented!()
-            //});
-            //Ok(Some(true))
-        //},
-        //kpat!(KeyCode::Char(',')) => {
-            //match self.plugin.as_mut() {
-                //Some(PluginKind::LV2(LV2Plugin { port_list, ref mut instance, .. })) => {
-                    //let index = port_list[self.selected].index;
-                    //if let Some(value) = instance.control_input(index) {
-                        //instance.set_control_input(index, value - 0.01);
-                    //}
-                //},
-                //_ => {}
-            //}
-            //Ok(Some(true))
-        //},
-        //kpat!(KeyCode::Char('.')) => {
-            //match self.plugin.as_mut() {
-                //Some(PluginKind::LV2(LV2Plugin { port_list, ref mut instance, .. })) => {
-                    //let index = port_list[self.selected].index;
-                    //if let Some(value) = instance.control_input(index) {
-                        //instance.set_control_input(index, value + 0.01);
-                    //}
-                //},
-                //_ => {}
-            //}
-            //Ok(Some(true))
-        //},
-        //kpat!(KeyCode::Char('g')) => {
-            //match self.plugin {
-                ////Some(PluginKind::LV2(ref mut plugin)) => {
-                    ////plugin.ui_thread = Some(run_lv2_ui(LV2PluginUI::new()?)?);
-                ////},
-                //Some(_) => unreachable!(),
-                //None => {}
-            //}
-            //Ok(Some(true))
-        //},
-        //_ => Ok(None)
-    //}
-//});
-
-//from_atom!("plugin/lv2" => |jack: &Jack, args| -> Plugin {
-    //let mut name = String::new();
-    //let mut path = String::new();
-    //atom!(atom in args {
-        //Atom::Map(map) => {
-            //if let Some(Atom::Str(n)) = map.get(&Atom::Key(":name")) {
-                //name = String::from(*n);
-            //}
-            //if let Some(Atom::Str(p)) = map.get(&Atom::Key(":path")) {
-                //path = String::from(*p);
-            //}
-        //},
-        //_ => panic!("unexpected in lv2 '{name}'"),
-    //});
-    //Plugin::new_lv2(jack, &name, &path)
-//});
diff --git a/crates/device/src/sampler.rs b/crates/device/src/sampler.rs
index 8ddfc4b6..6423684b 100644
--- a/crates/device/src/sampler.rs
+++ b/crates/device/src/sampler.rs
@@ -1,13 +1,5 @@
-#![feature(let_chains)]
+use crate::*;
 
-pub(crate) use ::tek_jack::{*, jack::*};
-pub(crate) use ::tek_midi::{*, midly::{*, live::*, num::*}};
-pub(crate) use ::tengri::{dsl::*, input::*, output::*, tui::{*, ratatui::prelude::*}};
-pub(crate) use std::sync::{Arc, RwLock, atomic::{AtomicUsize, Ordering::Relaxed}};
-pub(crate) use std::fs::File;
-pub(crate) use std::path::PathBuf;
-pub(crate) use std::error::Error;
-pub(crate) use std::ffi::OsString;
 pub(crate) use symphonia::{
     core::{
         formats::Packet,
@@ -19,7 +11,6 @@ pub(crate) use symphonia::{
     },
     default::get_codecs,
 };
-pub(crate) use ratatui::{prelude::Rect, widgets::{Widget, canvas::{Canvas, Line}}};
 
 mod sampler_api;    pub use self::sampler_api::*;
 mod sampler_audio;  pub use self::sampler_audio::*;
diff --git a/crates/engine/src/midi/clip.rs b/crates/device/src/sequencer.rs
similarity index 91%
rename from crates/engine/src/midi/clip.rs
rename to crates/device/src/sequencer.rs
index 95295621..eeec08e9 100644
--- a/crates/engine/src/midi/clip.rs
+++ b/crates/device/src/sequencer.rs
@@ -1,8 +1,9 @@
-mod clip_editor; pub use self::clip_editor::*;
-mod clip_launch; pub use self::clip_launch::*;
-mod clip_model;  pub use self::clip_model::*;
-mod clip_play;   pub use self::clip_play::*;
-mod clip_view;   pub use self::clip_view::*;
+use crate::*;
+
+mod seq_clip;   pub use self::seq_clip::*;
+mod seq_launch; pub use self::seq_launch::*;
+mod seq_model;  pub use self::seq_model::*;
+mod seq_view;   pub use self::seq_view::*;
 
 pub trait HasEditor {
     fn editor (&self) -> &Option<MidiEditor>;
diff --git a/crates/engine/src/midi/clip/clip_model.rs b/crates/device/src/sequencer/seq_clip.rs
similarity index 100%
rename from crates/engine/src/midi/clip/clip_model.rs
rename to crates/device/src/sequencer/seq_clip.rs
diff --git a/crates/engine/src/midi/clip/clip_launch.rs b/crates/device/src/sequencer/seq_launch.rs
similarity index 99%
rename from crates/engine/src/midi/clip/clip_launch.rs
rename to crates/device/src/sequencer/seq_launch.rs
index ee2f682e..48d30f1c 100644
--- a/crates/engine/src/midi/clip/clip_launch.rs
+++ b/crates/device/src/sequencer/seq_launch.rs
@@ -87,4 +87,3 @@ pub trait HasPlayClip: HasClock {
         FieldV(color, "Next:", format!("{} {}", time, name))
     }
 }
-
diff --git a/crates/device/src/sequencer/seq_model.rs b/crates/device/src/sequencer/seq_model.rs
new file mode 100644
index 00000000..004db566
--- /dev/null
+++ b/crates/device/src/sequencer/seq_model.rs
@@ -0,0 +1,452 @@
+//! MIDI player
+use crate::*;
+
+pub trait HasPlayer {
+    fn player (&self) -> &impl MidiPlayerApi;
+    fn player_mut (&mut self) -> &mut impl MidiPlayerApi;
+}
+
+#[macro_export] macro_rules! has_player {
+    (|$self:ident:$Struct:ident$(<$($L:lifetime),*$($T:ident$(:$U:path)?),*>)?|$cb:expr) => {
+        impl $(<$($L),*$($T $(: $U)?),*>)? HasPlayer for $Struct $(<$($L),*$($T),*>)? {
+            fn player (&$self) -> &impl MidiPlayerApi { &$cb }
+            fn player_mut (&mut $self) -> &mut impl MidiPlayerApi { &mut$cb }
+        }
+    }
+}
+
+pub trait MidiPlayerApi: MidiRecordApi + MidiPlaybackApi + Send + Sync {}
+
+impl MidiPlayerApi for MidiPlayer {}
+
+/// Contains state for playing a clip
+pub struct MidiPlayer {
+    /// State of clock and playhead
+    pub clock:       Clock,
+    /// Start time and clip being played
+    pub play_clip:   Option<(Moment, Option<Arc<RwLock<MidiClip>>>)>,
+    /// Start time and next clip
+    pub next_clip:   Option<(Moment, Option<Arc<RwLock<MidiClip>>>)>,
+    /// Play input through output.
+    pub monitoring:  bool,
+    /// Write input to sequence.
+    pub recording:   bool,
+    /// Overdub input to sequence.
+    pub overdub:     bool,
+    /// Send all notes off
+    pub reset:       bool, // TODO?: after Some(nframes)
+    /// Record from MIDI ports to current sequence.
+    pub midi_ins:    Vec<JackMidiIn>,
+    /// Play from current sequence to MIDI ports
+    pub midi_outs:   Vec<JackMidiOut>,
+    /// Notes currently held at input
+    pub notes_in:    Arc<RwLock<[bool; 128]>>,
+    /// Notes currently held at output
+    pub notes_out:   Arc<RwLock<[bool; 128]>>,
+    /// MIDI output buffer
+    pub note_buf:    Vec<u8>,
+}
+
+impl Default for MidiPlayer {
+    fn default () -> Self {
+        Self {
+            play_clip:  None,
+            next_clip:  None,
+            recording:  false,
+            monitoring: false,
+            overdub:    false,
+
+            notes_in:   RwLock::new([false;128]).into(),
+            notes_out:  RwLock::new([false;128]).into(),
+            note_buf:   vec![0;8],
+            reset:      true,
+
+            midi_ins:   vec![],
+            midi_outs:  vec![],
+            clock:      Clock::default(),
+        }
+    }
+}
+
+impl MidiPlayer {
+    pub fn new (
+        name:      impl AsRef<str>,
+        jack:      &Jack,
+        clock:     Option<&Clock>,
+        clip:      Option<&Arc<RwLock<MidiClip>>>,
+        midi_from: &[PortConnect],
+        midi_to:   &[PortConnect],
+    ) -> Usually<Self> {
+        let _name = name.as_ref();
+        let clock = clock.cloned().unwrap_or_default();
+        Ok(Self {
+            midi_ins:   vec![JackMidiIn::new(jack,  format!("M/{}", name.as_ref()), midi_from)?,],
+            midi_outs:  vec![JackMidiOut::new(jack, format!("{}/M", name.as_ref()), midi_to)?,  ],
+            play_clip:  clip.map(|clip|(Moment::zero(&clock.timebase), Some(clip.clone()))),
+            clock,
+            note_buf:   vec![0;8],
+            reset:      true,
+            recording:  false,
+            monitoring: false,
+            overdub:    false,
+            next_clip:  None,
+            notes_in:   RwLock::new([false;128]).into(),
+            notes_out:  RwLock::new([false;128]).into(),
+        })
+    }
+}
+
+impl std::fmt::Debug for MidiPlayer {
+    fn fmt (&self, f: &mut std::fmt::Formatter<'_>) -> std::result::Result<(), std::fmt::Error> {
+        f.debug_struct("MidiPlayer")
+            .field("clock",     &self.clock)
+            .field("play_clip", &self.play_clip)
+            .field("next_clip", &self.next_clip)
+            .finish()
+    }
+}
+
+has_clock!(|self: MidiPlayer|self.clock);
+
+impl HasMidiIns for MidiPlayer {
+    fn midi_ins (&self) -> &Vec<JackMidiIn> { &self.midi_ins }
+    fn midi_ins_mut (&mut self) -> &mut Vec<JackMidiIn> { &mut self.midi_ins }
+}
+
+impl HasMidiOuts for MidiPlayer {
+    fn midi_outs (&self) -> &Vec<JackMidiOut> { &self.midi_outs }
+    fn midi_outs_mut (&mut self) -> &mut Vec<JackMidiOut> { &mut self.midi_outs }
+    fn midi_note (&mut self) -> &mut Vec<u8> { &mut self.note_buf }
+}
+
+/// Hosts the JACK callback for a single MIDI player
+pub struct PlayerAudio<'a, T: MidiPlayerApi>(
+    /// Player
+    pub &'a mut T,
+    /// Note buffer
+    pub &'a mut Vec<u8>,
+    /// Note chunk buffer
+    pub &'a mut Vec<Vec<Vec<u8>>>,
+);
+
+/// JACK process callback for a sequencer's clip player/recorder.
+impl<T: MidiPlayerApi> Audio for PlayerAudio<'_, T> {
+    fn process (&mut self, _: &Client, scope: &ProcessScope) -> Control {
+        let model    = &mut self.0;
+        let note_buf = &mut self.1;
+        let midi_buf = &mut self.2;
+        // Clear output buffer(s)
+        model.clear(scope, midi_buf, false);
+        // Write chunk of clip to output, handle switchover
+        if model.play(scope, note_buf, midi_buf) {
+            model.switchover(scope, note_buf, midi_buf);
+        }
+        if model.has_midi_ins() {
+            if model.recording() || model.monitoring() {
+                // Record and/or monitor input
+                model.record(scope, midi_buf)
+            } else if model.has_midi_outs() && model.monitoring() {
+                // Monitor input to output
+                model.monitor(scope, midi_buf)
+            }
+        }
+        // Write to output port(s)
+        model.write(scope, midi_buf);
+        Control::Continue
+    }
+}
+
+impl MidiRecordApi for MidiPlayer {
+    fn recording (&self) -> bool {
+        self.recording
+    }
+    fn recording_mut (&mut self) -> &mut bool {
+        &mut self.recording
+    }
+    fn monitoring (&self) -> bool {
+        self.monitoring
+    }
+    fn monitoring_mut (&mut self) -> &mut bool {
+        &mut self.monitoring
+    }
+    fn overdub (&self) -> bool {
+        self.overdub
+    }
+    fn overdub_mut (&mut self) -> &mut bool {
+        &mut self.overdub
+    }
+    fn notes_in (&self) -> &Arc<RwLock<[bool; 128]>> {
+        &self.notes_in
+    }
+}
+
+impl MidiPlaybackApi for MidiPlayer {
+    fn notes_out (&self) -> &Arc<RwLock<[bool; 128]>> {
+        &self.notes_out
+    }
+}
+
+impl HasPlayClip for MidiPlayer {
+    fn reset (&self) -> bool {
+        self.reset
+    }
+    fn reset_mut (&mut self) -> &mut bool {
+        &mut self.reset
+    }
+    fn play_clip (&self) -> &Option<(Moment, Option<Arc<RwLock<MidiClip>>>)> {
+        &self.play_clip
+    }
+    fn play_clip_mut (&mut self) -> &mut Option<(Moment, Option<Arc<RwLock<MidiClip>>>)> {
+        &mut self.play_clip
+    }
+    fn next_clip (&self) -> &Option<(Moment, Option<Arc<RwLock<MidiClip>>>)> {
+        &self.next_clip
+    }
+    fn next_clip_mut (&mut self) -> &mut Option<(Moment, Option<Arc<RwLock<MidiClip>>>)> {
+        &mut self.next_clip
+    }
+}
+
+pub trait MidiRecordApi: HasClock + HasPlayClip + HasMidiIns {
+    fn notes_in (&self) -> &Arc<RwLock<[bool;128]>>;
+
+    fn recording (&self) -> bool;
+
+    fn recording_mut (&mut self) -> &mut bool;
+
+    fn toggle_record (&mut self) {
+        *self.recording_mut() = !self.recording();
+    }
+
+    fn monitoring (&self) -> bool;
+
+    fn monitoring_mut (&mut self) -> &mut bool;
+
+    fn toggle_monitor (&mut self) {
+        *self.monitoring_mut() = !self.monitoring();
+    }
+
+    fn overdub (&self) -> bool;
+
+    fn overdub_mut (&mut self) -> &mut bool;
+
+    fn toggle_overdub (&mut self) {
+        *self.overdub_mut() = !self.overdub();
+    }
+
+    fn monitor (&mut self, scope: &ProcessScope, midi_buf: &mut Vec<Vec<Vec<u8>>>) {
+        // For highlighting keys and note repeat
+        let notes_in = self.notes_in().clone();
+        let monitoring = self.monitoring();
+        for input in self.midi_ins_mut().iter() {
+            for (sample, event, bytes) in parse_midi_input(input.port().iter(scope)) {
+                if let LiveEvent::Midi { message, .. } = event {
+                    if monitoring {
+                        midi_buf[sample].push(bytes.to_vec());
+                    }
+                    // FIXME: don't lock on every event!
+                    update_keys(&mut notes_in.write().unwrap(), &message);
+                }
+            }
+        }
+    }
+
+    fn record (&mut self, scope: &ProcessScope, midi_buf: &mut Vec<Vec<Vec<u8>>>) {
+        if self.monitoring() {
+            self.monitor(scope, midi_buf);
+        }
+        if !self.clock().is_rolling() {
+            return
+        }
+        if let Some((started, ref clip)) = self.play_clip().clone() {
+            self.record_clip(scope, started, clip, midi_buf);
+        }
+        if let Some((_start_at, _clip)) = &self.next_clip() {
+            self.record_next();
+        }
+    }
+
+    fn record_clip (
+        &mut self,
+        scope:     &ProcessScope,
+        started:   Moment,
+        clip:      &Option<Arc<RwLock<MidiClip>>>,
+        _midi_buf: &mut Vec<Vec<Vec<u8>>>
+    ) {
+        if let Some(clip) = clip {
+            let sample0    = scope.last_frame_time() as usize;
+            let start      = started.sample.get() as usize;
+            let _recording = self.recording();
+            let timebase   = self.clock().timebase().clone();
+            let quant      = self.clock().quant.get();
+            let mut clip = clip.write().unwrap();
+            let length     = clip.length;
+            for input in self.midi_ins_mut().iter() {
+                for (sample, event, _bytes) in parse_midi_input(input.port().iter(scope)) {
+                    if let LiveEvent::Midi { message, .. } = event {
+                        clip.record_event({
+                            let sample    = (sample0 + sample - start) as f64;
+                            let pulse     = timebase.samples_to_pulse(sample);
+                            let quantized = (pulse / quant).round() * quant;
+                            quantized as usize % length
+                        }, message);
+                    }
+                }
+            }
+        }
+    }
+
+    fn record_next (&mut self) {
+        // TODO switch to next clip and record into it
+    }
+
+}
+
+pub trait MidiPlaybackApi: HasPlayClip + HasClock + HasMidiOuts {
+
+    fn notes_out (&self) -> &Arc<RwLock<[bool;128]>>;
+
+    /// Clear the section of the output buffer that we will be using,
+    /// emitting "all notes off" at start of buffer if requested.
+    fn clear (
+        &mut self, scope: &ProcessScope, out: &mut [Vec<Vec<u8>>], reset: bool
+    ) {
+        let n_frames = (scope.n_frames() as usize).min(out.len());
+        for frame in &mut out[0..n_frames] {
+            frame.clear();
+        }
+        if reset {
+            all_notes_off(out);
+        }
+    }
+
+    /// Output notes from clip to MIDI output ports.
+    fn play (
+        &mut self, scope: &ProcessScope, note_buf: &mut Vec<u8>, out: &mut [Vec<Vec<u8>>]
+    ) -> bool {
+        if !self.clock().is_rolling() {
+            return false
+        }
+        // If a clip is playing, write a chunk of MIDI events from it to the output buffer.
+        // If no clip is playing, prepare for switchover immediately.
+        self.play_clip().as_ref().map_or(true, |(started, clip)|{
+            self.play_chunk(scope, note_buf, out, started, clip)
+        })
+    }
+
+    /// Handle switchover from current to next playing clip.
+    fn switchover (
+        &mut self, scope: &ProcessScope, note_buf: &mut Vec<u8>, out: &mut [Vec<Vec<u8>>]
+    ) {
+        if !self.clock().is_rolling() {
+            return
+        }
+        let sample0 = scope.last_frame_time() as usize;
+        //let samples = scope.n_frames() as usize;
+        if let Some((start_at, clip)) = &self.next_clip() {
+            let start  = start_at.sample.get() as usize;
+            let sample = self.clock().started.read().unwrap()
+                .as_ref().unwrap().sample.get() as usize;
+            // If it's time to switch to the next clip:
+            if start <= sample0.saturating_sub(sample) {
+                // Samples elapsed since clip was supposed to start
+                let _skipped = sample0 - start;
+                // Switch over to enqueued clip
+                let started = Moment::from_sample(self.clock().timebase(), start as f64);
+                // Launch enqueued clip
+                *self.play_clip_mut() = Some((started, clip.clone()));
+                // Unset enqueuement (TODO: where to implement looping?)
+                *self.next_clip_mut() = None;
+                // Fill in remaining ticks of chunk from next clip.
+                self.play(scope, note_buf, out);
+            }
+        }
+    }
+
+    fn play_chunk (
+        &self,
+        scope:    &ProcessScope,
+        note_buf: &mut Vec<u8>,
+        out:      &mut [Vec<Vec<u8>>],
+        started:  &Moment,
+        clip:   &Option<Arc<RwLock<MidiClip>>>
+    ) -> bool {
+        // First sample to populate. Greater than 0 means that the first
+        // pulse of the clip falls somewhere in the middle of the chunk.
+        let sample = (scope.last_frame_time() as usize).saturating_sub(
+            started.sample.get() as usize +
+            self.clock().started.read().unwrap().as_ref().unwrap().sample.get() as usize
+        );
+        // Iterator that emits sample (index into output buffer at which to write MIDI event)
+        // paired with pulse (index into clip from which to take the MIDI event) for each
+        // sample of the output buffer that corresponds to a MIDI pulse.
+        let pulses = self.clock().timebase().pulses_between_samples(sample, sample + scope.n_frames() as usize);
+        // Notes active during current chunk.
+        let notes  = &mut self.notes_out().write().unwrap();
+        let length = clip.as_ref().map_or(0, |p|p.read().unwrap().length);
+        for (sample, pulse) in pulses {
+            // If a next clip is enqueued, and we're past the end of the current one,
+            // break the loop here (FIXME count pulse correctly)
+            let past_end = if clip.is_some() { pulse >= length } else { true };
+            if self.next_clip().is_some() && past_end {
+                return true
+            }
+            // If there's a currently playing clip, output notes from it to buffer:
+            if let Some(ref clip) = clip {
+                Self::play_pulse(clip, pulse, sample, note_buf, out, notes)
+            }
+        }
+        false
+    }
+
+    fn play_pulse (
+        clip:   &RwLock<MidiClip>,
+        pulse:    usize,
+        sample:   usize,
+        note_buf: &mut Vec<u8>,
+        out:      &mut [Vec<Vec<u8>>],
+        notes:    &mut [bool;128]
+    ) {
+        // Source clip from which the MIDI events will be taken.
+        let clip = clip.read().unwrap();
+        // Clip with zero length is not processed
+        if clip.length > 0 {
+            // Current pulse index in source clip
+            let pulse = pulse % clip.length;
+            // Output each MIDI event from clip at appropriate frames of output buffer:
+            for message in clip.notes[pulse].iter() {
+                // Clear output buffer for this MIDI event.
+                note_buf.clear();
+                // TODO: support MIDI channels other than CH1.
+                let channel = 0.into();
+                // Serialize MIDI event into message buffer.
+                LiveEvent::Midi { channel, message: *message }
+                    .write(note_buf)
+                    .unwrap();
+                // Append serialized message to output buffer.
+                out[sample].push(note_buf.clone());
+                // Update the list of currently held notes.
+                update_keys(&mut*notes, message);
+            }
+        }
+    }
+
+    /// Write a chunk of MIDI data from the output buffer to all assigned output ports.
+    fn write (&mut self, scope: &ProcessScope, out: &[Vec<Vec<u8>>]) {
+        let samples = scope.n_frames() as usize;
+        for port in self.midi_outs_mut().iter_mut() {
+            Self::write_port(&mut port.port_mut().writer(scope), samples, out)
+        }
+    }
+
+    /// Write a chunk of MIDI data from the output buffer to an output port.
+    fn write_port (writer: &mut MidiWriter, samples: usize, out: &[Vec<Vec<u8>>]) {
+        for (time, events) in out.iter().enumerate().take(samples) {
+            for bytes in events.iter() {
+                writer.write(&RawMidi { time: time as u32, bytes }).unwrap_or_else(|_|{
+                    panic!("Failed to write MIDI data: {bytes:?}");
+                });
+            }
+        }
+    }
+}
diff --git a/crates/engine/src/midi/clip/clip_view.rs b/crates/device/src/sequencer/seq_view.rs
similarity index 100%
rename from crates/engine/src/midi/clip/clip_view.rs
rename to crates/device/src/sequencer/seq_view.rs
diff --git a/crates/engine/src/jack.rs b/crates/engine/src/jack.rs
index 149ce0d2..390d4cb7 100644
--- a/crates/engine/src/jack.rs
+++ b/crates/engine/src/jack.rs
@@ -1,17 +1,18 @@
-#![feature(type_alias_impl_trait)]
-mod jack_client; pub use self::jack_client::*;
-mod jack_event; pub use self::jack_event::*;
-mod jack_port; pub use self::jack_port::*;
+use ::jack::{*, contrib::{*, ClosureProcessHandler}};
+    //contrib::ClosureProcessHandler,
+    //NotificationHandler,
+    //Client, AsyncClient, ClientOptions, ClientStatus,
+    //ProcessScope, Control, Frames,
+    //Port, PortId, PortSpec, PortFlags,
+    //Unowned, MidiIn, MidiOut, AudioIn, AudioOut,
+//};
+
 pub(crate) use PortConnectName::*;
 pub(crate) use PortConnectScope::*;
 pub(crate) use PortConnectStatus::*;
 pub(crate) use std::sync::{Arc, RwLock};
-pub use ::jack; pub(crate) use ::jack::{
-    //contrib::ClosureProcessHandler,
-    NotificationHandler,
-    Client, AsyncClient, ClientOptions, ClientStatus,
-    ProcessScope, Control, Frames,
-    Port, PortId, PortSpec, PortFlags,
-    Unowned, MidiIn, MidiOut, AudioIn, AudioOut,
-};
-pub(crate) type Usually<T> = Result<T, Box<dyn std::error::Error>>;
+
+mod jack_client; pub use self::jack_client::*;
+mod jack_event; pub use self::jack_event::*;
+mod jack_port; pub use self::jack_port::*;
+
diff --git a/crates/engine/src/jack/jack_client.rs b/crates/engine/src/jack/jack_client.rs
index ad89c7ae..5adb9a3e 100644
--- a/crates/engine/src/jack/jack_client.rs
+++ b/crates/engine/src/jack/jack_client.rs
@@ -1,5 +1,5 @@
 use crate::*;
-use ::jack::contrib::*;
+use super::*;
 use self::JackState::*;
 
 /// Things that can provide a [jack::Client] reference.
diff --git a/crates/engine/src/jack/jack_event.rs b/crates/engine/src/jack/jack_event.rs
index 43571f69..9ba6ad0f 100644
--- a/crates/engine/src/jack/jack_event.rs
+++ b/crates/engine/src/jack/jack_event.rs
@@ -1,4 +1,5 @@
 use crate::*;
+use super::*;
 
 /// Event enum for JACK events.
 #[derive(Debug, Clone, PartialEq)] pub enum JackEvent {
diff --git a/crates/engine/src/jack/jack_port.rs b/crates/engine/src/jack/jack_port.rs
index 5c34b748..7347269d 100644
--- a/crates/engine/src/jack/jack_port.rs
+++ b/crates/engine/src/jack/jack_port.rs
@@ -1,4 +1,5 @@
 use crate::*;
+use super::*;
 
 macro_rules! impl_port {
     ($Name:ident : $Spec:ident -> $Pair:ident |$jack:ident, $name:ident|$port:expr) => {
diff --git a/crates/engine/src/lib.rs b/crates/engine/src/lib.rs
new file mode 100644
index 00000000..a052ac7b
--- /dev/null
+++ b/crates/engine/src/lib.rs
@@ -0,0 +1,61 @@
+#![feature(type_alias_impl_trait)]
+
+mod jack;  pub use self::jack::*;
+mod time;  pub use self::time::*;
+mod note;  pub use self::note::*;
+mod midi;  pub use self::midi::*;
+
+pub(crate) use std::sync::{Arc, RwLock, atomic::{AtomicUsize, AtomicBool, Ordering::Relaxed}};
+pub(crate) use std::path::PathBuf;
+pub(crate) use std::fmt::Debug;
+pub(crate) use std::ops::{Add, Sub, Mul, Div, Rem};
+
+pub(crate) use ::tengri::input::*;
+pub(crate) use ::tengri::output::*;
+pub(crate) use ::tengri::dsl::*;
+pub(crate) use ::tengri::tui::*;
+pub(crate) use ::tengri::tui::ratatui::style::{Style, Stylize, Color};
+
+pub use ::atomic_float; pub(crate) use atomic_float::*;
+
+/// Standard result type.
+pub(crate) type Usually<T> = std::result::Result<T, Box<dyn std::error::Error>>;
+
+/// Standard optional result type.
+pub(crate) type Perhaps<T> = std::result::Result<Option<T>, Box<dyn std::error::Error>>;
+
+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) }
+}
+
+#[cfg(test)] #[test] fn test_time () -> Usually<()> {
+    // TODO!
+    Ok(())
+}
diff --git a/crates/engine/src/midi.rs b/crates/engine/src/midi.rs
index a617b9b3..fa9fa4f2 100644
--- a/crates/engine/src/midi.rs
+++ b/crates/engine/src/midi.rs
@@ -1,21 +1,60 @@
-pub(crate) use std::sync::{Arc, RwLock, atomic::{AtomicUsize, AtomicBool, Ordering::Relaxed}};
-pub(crate) use std::path::PathBuf;
-pub(crate) use std::fmt::Debug;
+use crate::*;
 
 pub use ::midly;
-pub(crate) use ::midly::{*, num::*, live::*};
+pub(crate) use ::midly::{
+    MidiMessage,
+    num::*,
+    live::*,
+};
 
-pub(crate) use ::tek_time::*;
-pub(crate) use ::tek_jack::{*, jack::*};
-pub(crate) use ::tengri::input::*;
-pub(crate) use ::tengri::output::*;
-pub(crate) use ::tengri::dsl::*;
-pub(crate) use ::tengri::tui::*;
-pub(crate) use ::tengri::tui::ratatui::style::{Style, Stylize, Color};
+/// Update notes_in array
+pub fn update_keys (keys: &mut[bool;128], message: &MidiMessage) {
+    match message {
+        MidiMessage::NoteOn  { key, .. } => { keys[key.as_int() as usize] = true; }
+        MidiMessage::NoteOff { key, .. } => { keys[key.as_int() as usize] = false; },
+        _ => {}
+    }
+}
 
-mod clip;  pub use self::clip::*;
-mod mode;  pub use self::mode::*;
-mod note;  pub use self::note::*;
-mod piano; pub use self::piano::*;
-mod pool;  pub use self::pool::*;
-mod port;  pub use self::port::*;
+/// Return boxed iterator of MIDI events
+pub fn parse_midi_input <'a> (input: ::jack::MidiIter<'a>) -> Box<dyn Iterator<Item=(usize, LiveEvent<'a>, &'a [u8])> + 'a> {
+    Box::new(input.map(|::jack::RawMidi { time, bytes }|(
+        time as usize,
+        LiveEvent::parse(bytes).unwrap(),
+        bytes
+    )))
+}
+
+/// Add "all notes off" to the start of a buffer.
+pub fn all_notes_off (output: &mut [Vec<Vec<u8>>]) {
+    let mut buf = vec![];
+    let msg = MidiMessage::Controller { controller: 123.into(), value: 0.into() };
+    let evt = LiveEvent::Midi { channel: 0.into(), message: msg };
+    evt.write(&mut buf).unwrap();
+    output[0].push(buf);
+}
+
+/// Trait for thing that may receive MIDI.
+pub trait HasMidiIns {
+    fn midi_ins (&self) -> &Vec<JackMidiIn>;
+
+    fn midi_ins_mut (&mut self) -> &mut Vec<JackMidiIn>;
+
+    fn has_midi_ins (&self) -> bool {
+        !self.midi_ins().is_empty()
+    }
+}
+
+/// Trait for thing that may output MIDI.
+pub trait HasMidiOuts {
+    fn midi_outs (&self) -> &Vec<JackMidiOut>;
+
+    fn midi_outs_mut (&mut self) -> &mut Vec<JackMidiOut>;
+
+    fn has_midi_outs (&self) -> bool {
+        !self.midi_outs().is_empty()
+    }
+
+    /// Buffer for serializing a MIDI event. FIXME rename
+    fn midi_note (&mut self) -> &mut Vec<u8>;
+}
diff --git a/crates/engine/src/midi/clip/clip_play.rs b/crates/engine/src/midi/clip/clip_play.rs
deleted file mode 100644
index b7df1fe9..00000000
--- a/crates/engine/src/midi/clip/clip_play.rs
+++ /dev/null
@@ -1,208 +0,0 @@
-//! MIDI player
-use crate::*;
-
-pub trait HasPlayer {
-    fn player (&self) -> &impl MidiPlayerApi;
-    fn player_mut (&mut self) -> &mut impl MidiPlayerApi;
-}
-
-#[macro_export] macro_rules! has_player {
-    (|$self:ident:$Struct:ident$(<$($L:lifetime),*$($T:ident$(:$U:path)?),*>)?|$cb:expr) => {
-        impl $(<$($L),*$($T $(: $U)?),*>)? HasPlayer for $Struct $(<$($L),*$($T),*>)? {
-            fn player (&$self) -> &impl MidiPlayerApi { &$cb }
-            fn player_mut (&mut $self) -> &mut impl MidiPlayerApi { &mut$cb }
-        }
-    }
-}
-
-pub trait MidiPlayerApi: MidiRecordApi + MidiPlaybackApi + Send + Sync {}
-
-impl MidiPlayerApi for MidiPlayer {}
-
-/// Contains state for playing a clip
-pub struct MidiPlayer {
-    /// State of clock and playhead
-    pub clock:       Clock,
-    /// Start time and clip being played
-    pub play_clip:   Option<(Moment, Option<Arc<RwLock<MidiClip>>>)>,
-    /// Start time and next clip
-    pub next_clip:   Option<(Moment, Option<Arc<RwLock<MidiClip>>>)>,
-    /// Play input through output.
-    pub monitoring:  bool,
-    /// Write input to sequence.
-    pub recording:   bool,
-    /// Overdub input to sequence.
-    pub overdub:     bool,
-    /// Send all notes off
-    pub reset:       bool, // TODO?: after Some(nframes)
-    /// Record from MIDI ports to current sequence.
-    pub midi_ins:    Vec<JackMidiIn>,
-    /// Play from current sequence to MIDI ports
-    pub midi_outs:   Vec<JackMidiOut>,
-    /// Notes currently held at input
-    pub notes_in:    Arc<RwLock<[bool; 128]>>,
-    /// Notes currently held at output
-    pub notes_out:   Arc<RwLock<[bool; 128]>>,
-    /// MIDI output buffer
-    pub note_buf:    Vec<u8>,
-}
-
-impl Default for MidiPlayer {
-    fn default () -> Self {
-        Self {
-            play_clip:  None,
-            next_clip:  None,
-            recording:  false,
-            monitoring: false,
-            overdub:    false,
-
-            notes_in:   RwLock::new([false;128]).into(),
-            notes_out:  RwLock::new([false;128]).into(),
-            note_buf:   vec![0;8],
-            reset:      true,
-
-            midi_ins:   vec![],
-            midi_outs:  vec![],
-            clock:      Clock::default(),
-        }
-    }
-}
-
-impl MidiPlayer {
-    pub fn new (
-        name:      impl AsRef<str>,
-        jack:      &Jack,
-        clock:     Option<&Clock>,
-        clip:      Option<&Arc<RwLock<MidiClip>>>,
-        midi_from: &[PortConnect],
-        midi_to:   &[PortConnect],
-    ) -> Usually<Self> {
-        let _name = name.as_ref();
-        let clock = clock.cloned().unwrap_or_default();
-        Ok(Self {
-            midi_ins:   vec![JackMidiIn::new(jack,  format!("M/{}", name.as_ref()), midi_from)?,],
-            midi_outs:  vec![JackMidiOut::new(jack, format!("{}/M", name.as_ref()), midi_to)?,  ],
-            play_clip:  clip.map(|clip|(Moment::zero(&clock.timebase), Some(clip.clone()))),
-            clock,
-            note_buf:   vec![0;8],
-            reset:      true,
-            recording:  false,
-            monitoring: false,
-            overdub:    false,
-            next_clip:  None,
-            notes_in:   RwLock::new([false;128]).into(),
-            notes_out:  RwLock::new([false;128]).into(),
-        })
-    }
-}
-
-impl std::fmt::Debug for MidiPlayer {
-    fn fmt (&self, f: &mut std::fmt::Formatter<'_>) -> std::result::Result<(), std::fmt::Error> {
-        f.debug_struct("MidiPlayer")
-            .field("clock",     &self.clock)
-            .field("play_clip", &self.play_clip)
-            .field("next_clip", &self.next_clip)
-            .finish()
-    }
-}
-
-has_clock!(|self: MidiPlayer|self.clock);
-
-impl HasMidiIns for MidiPlayer {
-    fn midi_ins (&self) -> &Vec<JackMidiIn> { &self.midi_ins }
-    fn midi_ins_mut (&mut self) -> &mut Vec<JackMidiIn> { &mut self.midi_ins }
-}
-
-impl HasMidiOuts for MidiPlayer {
-    fn midi_outs (&self) -> &Vec<JackMidiOut> { &self.midi_outs }
-    fn midi_outs_mut (&mut self) -> &mut Vec<JackMidiOut> { &mut self.midi_outs }
-    fn midi_note (&mut self) -> &mut Vec<u8> { &mut self.note_buf }
-}
-
-/// Hosts the JACK callback for a single MIDI player
-pub struct PlayerAudio<'a, T: MidiPlayerApi>(
-    /// Player
-    pub &'a mut T,
-    /// Note buffer
-    pub &'a mut Vec<u8>,
-    /// Note chunk buffer
-    pub &'a mut Vec<Vec<Vec<u8>>>,
-);
-
-/// JACK process callback for a sequencer's clip player/recorder.
-impl<T: MidiPlayerApi> Audio for PlayerAudio<'_, T> {
-    fn process (&mut self, _: &Client, scope: &ProcessScope) -> Control {
-        let model    = &mut self.0;
-        let note_buf = &mut self.1;
-        let midi_buf = &mut self.2;
-        // Clear output buffer(s)
-        model.clear(scope, midi_buf, false);
-        // Write chunk of clip to output, handle switchover
-        if model.play(scope, note_buf, midi_buf) {
-            model.switchover(scope, note_buf, midi_buf);
-        }
-        if model.has_midi_ins() {
-            if model.recording() || model.monitoring() {
-                // Record and/or monitor input
-                model.record(scope, midi_buf)
-            } else if model.has_midi_outs() && model.monitoring() {
-                // Monitor input to output
-                model.monitor(scope, midi_buf)
-            }
-        }
-        // Write to output port(s)
-        model.write(scope, midi_buf);
-        Control::Continue
-    }
-}
-
-impl MidiRecordApi for MidiPlayer {
-    fn recording (&self) -> bool {
-        self.recording
-    }
-    fn recording_mut (&mut self) -> &mut bool {
-        &mut self.recording
-    }
-    fn monitoring (&self) -> bool {
-        self.monitoring
-    }
-    fn monitoring_mut (&mut self) -> &mut bool {
-        &mut self.monitoring
-    }
-    fn overdub (&self) -> bool {
-        self.overdub
-    }
-    fn overdub_mut (&mut self) -> &mut bool {
-        &mut self.overdub
-    }
-    fn notes_in (&self) -> &Arc<RwLock<[bool; 128]>> {
-        &self.notes_in
-    }
-}
-
-impl MidiPlaybackApi for MidiPlayer {
-    fn notes_out (&self) -> &Arc<RwLock<[bool; 128]>> {
-        &self.notes_out
-    }
-}
-
-impl HasPlayClip for MidiPlayer {
-    fn reset (&self) -> bool {
-        self.reset
-    }
-    fn reset_mut (&mut self) -> &mut bool {
-        &mut self.reset
-    }
-    fn play_clip (&self) -> &Option<(Moment, Option<Arc<RwLock<MidiClip>>>)> {
-        &self.play_clip
-    }
-    fn play_clip_mut (&mut self) -> &mut Option<(Moment, Option<Arc<RwLock<MidiClip>>>)> {
-        &mut self.play_clip
-    }
-    fn next_clip (&self) -> &Option<(Moment, Option<Arc<RwLock<MidiClip>>>)> {
-        &self.next_clip
-    }
-    fn next_clip_mut (&mut self) -> &mut Option<(Moment, Option<Arc<RwLock<MidiClip>>>)> {
-        &mut self.next_clip
-    }
-}
diff --git a/crates/engine/src/midi/piano.rs b/crates/engine/src/midi/piano.rs
deleted file mode 100644
index ea7b9152..00000000
--- a/crates/engine/src/midi/piano.rs
+++ /dev/null
@@ -1,2 +0,0 @@
-mod piano_h; pub use self::piano_h::*;
-mod piano_v; pub use self::piano_v::*;
diff --git a/crates/engine/src/midi/piano/piano_v.rs b/crates/engine/src/midi/piano/piano_v.rs
deleted file mode 100644
index 27bd1d5e..00000000
--- a/crates/engine/src/midi/piano/piano_v.rs
+++ /dev/null
@@ -1,34 +0,0 @@
-use crate::*;
-use Color::*;
-pub struct OctaveVertical {
-    on:     [bool; 12],
-    colors: [Color; 3]
-}
-impl Default for OctaveVertical {
-    fn default () -> Self {
-        Self {
-            on:     [false; 12],
-            colors: [Rgb(255,255,255), Rgb(0,0,0), Rgb(255,0,0)]
-        }
-    }
-}
-impl OctaveVertical {
-    fn color (&self, pitch: usize) -> Color {
-        let pitch = pitch % 12;
-        self.colors[if self.on[pitch] { 2 } else {
-            match pitch { 0 | 2 | 4 | 5 | 6 | 8 | 10 => 0, _ => 1 }
-        }]
-    }
-}
-impl Content<TuiOut> for OctaveVertical {
-    fn content (&self) -> impl Render<TuiOut> {
-        row!(
-            Tui::fg_bg(self.color(0),  self.color(1),  "▙"),
-            Tui::fg_bg(self.color(2),  self.color(3),  "▙"),
-            Tui::fg_bg(self.color(4),  self.color(5),  "▌"),
-            Tui::fg_bg(self.color(6),  self.color(7),  "▟"),
-            Tui::fg_bg(self.color(8),  self.color(9),  "▟"),
-            Tui::fg_bg(self.color(10), self.color(11), "▟"),
-        )
-    }
-}
diff --git a/crates/engine/src/midi/port.rs b/crates/engine/src/midi/port.rs
deleted file mode 100644
index 25977123..00000000
--- a/crates/engine/src/midi/port.rs
+++ /dev/null
@@ -1,31 +0,0 @@
-use crate::*;
-
-mod port_in;  pub use self::port_in::*;
-mod port_out; pub use self::port_out::*;
-
-/// Update notes_in array
-pub fn update_keys (keys: &mut[bool;128], message: &MidiMessage) {
-    match message {
-        MidiMessage::NoteOn  { key, .. } => { keys[key.as_int() as usize] = true; }
-        MidiMessage::NoteOff { key, .. } => { keys[key.as_int() as usize] = false; },
-        _ => {}
-    }
-}
-
-/// Return boxed iterator of MIDI events
-pub fn parse_midi_input <'a> (input: MidiIter<'a>) -> Box<dyn Iterator<Item=(usize, LiveEvent<'a>, &'a [u8])> + 'a> {
-    Box::new(input.map(|RawMidi { time, bytes }|(
-        time as usize,
-        LiveEvent::parse(bytes).unwrap(),
-        bytes
-    )))
-}
-
-/// Add "all notes off" to the start of a buffer.
-pub fn all_notes_off (output: &mut [Vec<Vec<u8>>]) {
-    let mut buf = vec![];
-    let msg = MidiMessage::Controller { controller: 123.into(), value: 0.into() };
-    let evt = LiveEvent::Midi { channel: 0.into(), message: msg };
-    evt.write(&mut buf).unwrap();
-    output[0].push(buf);
-}
diff --git a/crates/engine/src/midi/port/port_in.rs b/crates/engine/src/midi/port/port_in.rs
deleted file mode 100644
index abbd1390..00000000
--- a/crates/engine/src/midi/port/port_in.rs
+++ /dev/null
@@ -1,107 +0,0 @@
-use crate::*;
-
-/// Trait for thing that may receive MIDI.
-pub trait HasMidiIns {
-    fn midi_ins (&self) -> &Vec<JackMidiIn>;
-
-    fn midi_ins_mut (&mut self) -> &mut Vec<JackMidiIn>;
-
-    fn has_midi_ins (&self) -> bool {
-        !self.midi_ins().is_empty()
-    }
-}
-
-pub trait MidiRecordApi: HasClock + HasPlayClip + HasMidiIns {
-    fn notes_in (&self) -> &Arc<RwLock<[bool;128]>>;
-
-    fn recording (&self) -> bool;
-
-    fn recording_mut (&mut self) -> &mut bool;
-
-    fn toggle_record (&mut self) {
-        *self.recording_mut() = !self.recording();
-    }
-
-    fn monitoring (&self) -> bool;
-
-    fn monitoring_mut (&mut self) -> &mut bool;
-
-    fn toggle_monitor (&mut self) {
-        *self.monitoring_mut() = !self.monitoring();
-    }
-
-    fn overdub (&self) -> bool;
-
-    fn overdub_mut (&mut self) -> &mut bool;
-
-    fn toggle_overdub (&mut self) {
-        *self.overdub_mut() = !self.overdub();
-    }
-
-    fn monitor (&mut self, scope: &ProcessScope, midi_buf: &mut Vec<Vec<Vec<u8>>>) {
-        // For highlighting keys and note repeat
-        let notes_in = self.notes_in().clone();
-        let monitoring = self.monitoring();
-        for input in self.midi_ins_mut().iter() {
-            for (sample, event, bytes) in parse_midi_input(input.port().iter(scope)) {
-                if let LiveEvent::Midi { message, .. } = event {
-                    if monitoring {
-                        midi_buf[sample].push(bytes.to_vec());
-                    }
-                    // FIXME: don't lock on every event!
-                    update_keys(&mut notes_in.write().unwrap(), &message);
-                }
-            }
-        }
-    }
-
-    fn record (&mut self, scope: &ProcessScope, midi_buf: &mut Vec<Vec<Vec<u8>>>) {
-        if self.monitoring() {
-            self.monitor(scope, midi_buf);
-        }
-        if !self.clock().is_rolling() {
-            return
-        }
-        if let Some((started, ref clip)) = self.play_clip().clone() {
-            self.record_clip(scope, started, clip, midi_buf);
-        }
-        if let Some((_start_at, _clip)) = &self.next_clip() {
-            self.record_next();
-        }
-    }
-
-    fn record_clip (
-        &mut self,
-        scope:     &ProcessScope,
-        started:   Moment,
-        clip:      &Option<Arc<RwLock<MidiClip>>>,
-        _midi_buf: &mut Vec<Vec<Vec<u8>>>
-    ) {
-        if let Some(clip) = clip {
-            let sample0    = scope.last_frame_time() as usize;
-            let start      = started.sample.get() as usize;
-            let _recording = self.recording();
-            let timebase   = self.clock().timebase().clone();
-            let quant      = self.clock().quant.get();
-            let mut clip = clip.write().unwrap();
-            let length     = clip.length;
-            for input in self.midi_ins_mut().iter() {
-                for (sample, event, _bytes) in parse_midi_input(input.port().iter(scope)) {
-                    if let LiveEvent::Midi { message, .. } = event {
-                        clip.record_event({
-                            let sample    = (sample0 + sample - start) as f64;
-                            let pulse     = timebase.samples_to_pulse(sample);
-                            let quantized = (pulse / quant).round() * quant;
-                            quantized as usize % length
-                        }, message);
-                    }
-                }
-            }
-        }
-    }
-
-    fn record_next (&mut self) {
-        // TODO switch to next clip and record into it
-    }
-
-}
diff --git a/crates/engine/src/midi/port/port_out.rs b/crates/engine/src/midi/port/port_out.rs
deleted file mode 100644
index 159d11c6..00000000
--- a/crates/engine/src/midi/port/port_out.rs
+++ /dev/null
@@ -1,164 +0,0 @@
-use crate::*;
-
-/// Trait for thing that may output MIDI.
-pub trait HasMidiOuts {
-    fn midi_outs (&self) -> &Vec<JackMidiOut>;
-
-    fn midi_outs_mut (&mut self) -> &mut Vec<JackMidiOut>;
-
-    fn has_midi_outs (&self) -> bool {
-        !self.midi_outs().is_empty()
-    }
-
-    /// Buffer for serializing a MIDI event. FIXME rename
-    fn midi_note (&mut self) -> &mut Vec<u8>;
-}
-
-pub trait MidiPlaybackApi: HasPlayClip + HasClock + HasMidiOuts {
-
-    fn notes_out (&self) -> &Arc<RwLock<[bool;128]>>;
-
-    /// Clear the section of the output buffer that we will be using,
-    /// emitting "all notes off" at start of buffer if requested.
-    fn clear (
-        &mut self, scope: &ProcessScope, out: &mut [Vec<Vec<u8>>], reset: bool
-    ) {
-        let n_frames = (scope.n_frames() as usize).min(out.len());
-        for frame in &mut out[0..n_frames] {
-            frame.clear();
-        }
-        if reset {
-            all_notes_off(out);
-        }
-    }
-
-    /// Output notes from clip to MIDI output ports.
-    fn play (
-        &mut self, scope: &ProcessScope, note_buf: &mut Vec<u8>, out: &mut [Vec<Vec<u8>>]
-    ) -> bool {
-        if !self.clock().is_rolling() {
-            return false
-        }
-        // If a clip is playing, write a chunk of MIDI events from it to the output buffer.
-        // If no clip is playing, prepare for switchover immediately.
-        self.play_clip().as_ref().map_or(true, |(started, clip)|{
-            self.play_chunk(scope, note_buf, out, started, clip)
-        })
-    }
-
-    /// Handle switchover from current to next playing clip.
-    fn switchover (
-        &mut self, scope: &ProcessScope, note_buf: &mut Vec<u8>, out: &mut [Vec<Vec<u8>>]
-    ) {
-        if !self.clock().is_rolling() {
-            return
-        }
-        let sample0 = scope.last_frame_time() as usize;
-        //let samples = scope.n_frames() as usize;
-        if let Some((start_at, clip)) = &self.next_clip() {
-            let start  = start_at.sample.get() as usize;
-            let sample = self.clock().started.read().unwrap()
-                .as_ref().unwrap().sample.get() as usize;
-            // If it's time to switch to the next clip:
-            if start <= sample0.saturating_sub(sample) {
-                // Samples elapsed since clip was supposed to start
-                let _skipped = sample0 - start;
-                // Switch over to enqueued clip
-                let started = Moment::from_sample(self.clock().timebase(), start as f64);
-                // Launch enqueued clip
-                *self.play_clip_mut() = Some((started, clip.clone()));
-                // Unset enqueuement (TODO: where to implement looping?)
-                *self.next_clip_mut() = None;
-                // Fill in remaining ticks of chunk from next clip.
-                self.play(scope, note_buf, out);
-            }
-        }
-    }
-
-    fn play_chunk (
-        &self,
-        scope:    &ProcessScope,
-        note_buf: &mut Vec<u8>,
-        out:      &mut [Vec<Vec<u8>>],
-        started:  &Moment,
-        clip:   &Option<Arc<RwLock<MidiClip>>>
-    ) -> bool {
-        // First sample to populate. Greater than 0 means that the first
-        // pulse of the clip falls somewhere in the middle of the chunk.
-        let sample = (scope.last_frame_time() as usize).saturating_sub(
-            started.sample.get() as usize +
-            self.clock().started.read().unwrap().as_ref().unwrap().sample.get() as usize
-        );
-        // Iterator that emits sample (index into output buffer at which to write MIDI event)
-        // paired with pulse (index into clip from which to take the MIDI event) for each
-        // sample of the output buffer that corresponds to a MIDI pulse.
-        let pulses = self.clock().timebase().pulses_between_samples(sample, sample + scope.n_frames() as usize);
-        // Notes active during current chunk.
-        let notes  = &mut self.notes_out().write().unwrap();
-        let length = clip.as_ref().map_or(0, |p|p.read().unwrap().length);
-        for (sample, pulse) in pulses {
-            // If a next clip is enqueued, and we're past the end of the current one,
-            // break the loop here (FIXME count pulse correctly)
-            let past_end = if clip.is_some() { pulse >= length } else { true };
-            if self.next_clip().is_some() && past_end {
-                return true
-            }
-            // If there's a currently playing clip, output notes from it to buffer:
-            if let Some(ref clip) = clip {
-                Self::play_pulse(clip, pulse, sample, note_buf, out, notes)
-            }
-        }
-        false
-    }
-
-    fn play_pulse (
-        clip:   &RwLock<MidiClip>,
-        pulse:    usize,
-        sample:   usize,
-        note_buf: &mut Vec<u8>,
-        out:      &mut [Vec<Vec<u8>>],
-        notes:    &mut [bool;128]
-    ) {
-        // Source clip from which the MIDI events will be taken.
-        let clip = clip.read().unwrap();
-        // Clip with zero length is not processed
-        if clip.length > 0 {
-            // Current pulse index in source clip
-            let pulse = pulse % clip.length;
-            // Output each MIDI event from clip at appropriate frames of output buffer:
-            for message in clip.notes[pulse].iter() {
-                // Clear output buffer for this MIDI event.
-                note_buf.clear();
-                // TODO: support MIDI channels other than CH1.
-                let channel = 0.into();
-                // Serialize MIDI event into message buffer.
-                LiveEvent::Midi { channel, message: *message }
-                    .write(note_buf)
-                    .unwrap();
-                // Append serialized message to output buffer.
-                out[sample].push(note_buf.clone());
-                // Update the list of currently held notes.
-                update_keys(&mut*notes, message);
-            }
-        }
-    }
-
-    /// Write a chunk of MIDI data from the output buffer to all assigned output ports.
-    fn write (&mut self, scope: &ProcessScope, out: &[Vec<Vec<u8>>]) {
-        let samples = scope.n_frames() as usize;
-        for port in self.midi_outs_mut().iter_mut() {
-            Self::write_port(&mut port.port_mut().writer(scope), samples, out)
-        }
-    }
-
-    /// Write a chunk of MIDI data from the output buffer to an output port.
-    fn write_port (writer: &mut MidiWriter, samples: usize, out: &[Vec<Vec<u8>>]) {
-        for (time, events) in out.iter().enumerate().take(samples) {
-            for bytes in events.iter() {
-                writer.write(&RawMidi { time: time as u32, bytes }).unwrap_or_else(|_|{
-                    panic!("Failed to write MIDI data: {bytes:?}");
-                });
-            }
-        }
-    }
-}
diff --git a/crates/engine/src/midi/note.rs b/crates/engine/src/note.rs
similarity index 100%
rename from crates/engine/src/midi/note.rs
rename to crates/engine/src/note.rs
diff --git a/crates/engine/src/midi/note/note_pitch.rs b/crates/engine/src/note/note_pitch.rs
similarity index 100%
rename from crates/engine/src/midi/note/note_pitch.rs
rename to crates/engine/src/note/note_pitch.rs
diff --git a/crates/engine/src/midi/note/note_point.rs b/crates/engine/src/note/note_point.rs
similarity index 100%
rename from crates/engine/src/midi/note/note_point.rs
rename to crates/engine/src/note/note_point.rs
diff --git a/crates/engine/src/midi/note/note_range.rs b/crates/engine/src/note/note_range.rs
similarity index 100%
rename from crates/engine/src/midi/note/note_range.rs
rename to crates/engine/src/note/note_range.rs
diff --git a/crates/engine/src/time.rs b/crates/engine/src/time.rs
index 2ad81860..9d4e7459 100644
--- a/crates/engine/src/time.rs
+++ b/crates/engine/src/time.rs
@@ -1,5 +1,3 @@
-mod clock; pub use self::clock::*;
-
 mod time_moment;       pub use self::time_moment::*;
 mod time_note;         pub use self::time_note::*;
 mod time_perf;         pub use self::time_perf::*;
@@ -9,50 +7,3 @@ mod time_sample_rate;  pub use self::time_sample_rate::*;
 mod time_timebase;     pub use self::time_timebase::*;
 mod time_unit;         pub use self::time_unit::*;
 mod time_usec;         pub use self::time_usec::*;
-
-pub(crate) use ::tek_jack::{*, jack::{*, contrib::*}};
-pub(crate) use std::sync::{Arc, RwLock, atomic::{AtomicBool, AtomicUsize, Ordering::*}};
-pub(crate) use std::ops::{Add, Sub, Mul, Div, Rem};
-pub(crate) use ::tengri::{input::*, dsl::*};
-pub use ::atomic_float; pub(crate) use atomic_float::*;
-
-/// Standard result type.
-pub(crate) type Usually<T> = Result<T, Box<dyn std::error::Error>>;
-/// Standard optional result type.
-pub(crate) type Perhaps<T> = Result<Option<T>, Box<dyn std::error::Error>>;
-
-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) }
-}
-
-#[cfg(test)] #[test] fn test_time () -> Usually<()> {
-    // TODO!
-    Ok(())
-}
diff --git a/crates/engine/src/time/time_perf.rs b/crates/engine/src/time/time_perf.rs
index c435fdff..f14bcc66 100644
--- a/crates/engine/src/time/time_perf.rs
+++ b/crates/engine/src/time/time_perf.rs
@@ -1,5 +1,6 @@
 use crate::*;
 use tengri::tui::PerfModel;
+use ::jack::ProcessScope;
 
 pub trait JackPerfModel {
     fn update_from_jack_scope (&self, t0: Option<u64>, scope: &ProcessScope);