diff --git a/crates/app/src/api.rs b/crates/app/src/api.rs
index b0db4c6f..aa33ef34 100644
--- a/crates/app/src/api.rs
+++ b/crates/app/src/api.rs
@@ -17,8 +17,7 @@ handle!(TuiIn: |self: Tek, input|Ok(if let Some(command) = self.config.keys.comm
     None
 }));
 
-#[tengri_proc::expose]
-impl Tek {
+#[tengri_proc::expose] impl Tek {
     fn focus_editor (&self) -> bool {
         self.is_editing()
     }
@@ -161,8 +160,7 @@ impl Tek {
     }
 }
 
-#[tengri_proc::expose]
-impl MidiPool {
+#[tengri_proc::expose] impl MidiPool {
     fn clip_new (&self) -> MidiClip {
         self.new_clip()
     }
@@ -186,8 +184,7 @@ impl MidiPool {
     }
 }
 
-#[tengri_proc::expose]
-impl MidiEditor {
+#[tengri_proc::expose] impl MidiEditor {
     fn time_lock (&self) -> bool {
         self.get_time_lock()
     }
@@ -256,27 +253,26 @@ impl MidiEditor {
     }
 }
 
-#[tengri_proc::command(Tek)]
-impl TekCommand {
-    fn toggle_help (&self, tek: &mut Tek, value: bool) -> Perhaps<Self> {
+#[tengri_proc::command(Tek)] impl TekCommand {
+    fn toggle_help (tek: &mut Tek, value: bool) -> Perhaps<Self> {
         tek.toggle_dialog(Some(Dialog::Help));
         Ok(None)
     }
-    fn toggle_menu (&self, tek: &mut Tek, value: bool) -> Perhaps<Self> {
+    fn toggle_menu (tek: &mut Tek, value: bool) -> Perhaps<Self> {
         tek.toggle_dialog(Some(Dialog::Menu));
         Ok(None)
     }
-    fn toggle_edit (&self, tek: &mut Tek, value: bool) -> Perhaps<Self> {
+    fn toggle_edit (tek: &mut Tek, value: bool) -> Perhaps<Self> {
         tek.toggle_editor(Some(value));
         Ok(None)
     }
-    fn editor (&self, tek: &mut Tek, command: MidiEditCommand) -> Perhaps<Self> {
+    fn editor (tek: &mut Tek, command: MidiEditCommand) -> Perhaps<Self> {
         Ok(tek.editor.as_mut().map(|editor|command.execute(editor))
             .transpose()?
             .flatten()
             .map(|undo|Self::Editor { command: undo }))
     }
-    fn pool (&self, tek: &mut Tek, command: PoolCommand) -> Perhaps<Self> {
+    fn pool (tek: &mut Tek, command: PoolCommand) -> Perhaps<Self> {
         Ok(if let Some(pool) = tek.pool.as_mut() {
             let undo = command.clone().delegate(pool, |command|TekCommand::Pool{command})?;
             // update linked editor after pool action
@@ -293,53 +289,53 @@ impl TekCommand {
             None
         })
     }
-    fn sampler (&self, tek: &mut Tek, ref command: SamplerCommand) -> Perhaps<Self> {
+    fn sampler (tek: &mut Tek, command: SamplerCommand) -> Perhaps<Self> {
         Ok(tek.sampler_mut()
             .map(|s|command.delegate(s, |command|Self::Sampler{command}))
             .transpose()?
             .flatten())
     }
-    fn scene (&self, tek: &mut Tek, command: SceneCommand) -> Perhaps<Self> {
+    fn scene (tek: &mut Tek, command: SceneCommand) -> Perhaps<Self> {
         Ok(command.delegate(tek, |command|Self::Scene{command})?)
     }
-    fn track (&self, tek: &mut Tek, command: TrackCommand) -> Perhaps<Self> {
+    fn track (tek: &mut Tek, command: TrackCommand) -> Perhaps<Self> {
         Ok(command.delegate(tek, |command|Self::Track{command})?)
     }
-    fn input (&self, tek: &mut Tek, command: InputCommand) -> Perhaps<Self> {
+    fn input (tek: &mut Tek, command: InputCommand) -> Perhaps<Self> {
         Ok(command.delegate(tek, |command|Self::Input{command})?)
     }
-    fn output (&self, tek: &mut Tek, command: OutputCommand) -> Perhaps<Self> {
+    fn output (tek: &mut Tek, command: OutputCommand) -> Perhaps<Self> {
         Ok(command.delegate(tek, |command|Self::Output{command})?)
     }
-    fn clip (&self, tek: &mut Tek, command: ClipCommand) -> Perhaps<Self> {
+    fn clip (tek: &mut Tek, command: ClipCommand) -> Perhaps<Self> {
         Ok(command.delegate(tek, |command|Self::Clip{command})?)
     }
-    fn clock (&self, tek: &mut Tek, command: ClockCommand) -> Perhaps<Self> {
-        Ok(command.delegate(tek, |command|Self::Clock{command})?)
+    fn clock (tek: &mut Tek, command: ClockCommand) -> Perhaps<Self> {
+        Ok(command.execute(&mut tek.clock)?.map(|command|Self::Clock{command}))
     }
-    fn device (&self, tek: &mut Tek, command: DeviceCommand) -> Perhaps<Self> {
+    fn device (tek: &mut Tek, command: DeviceCommand) -> Perhaps<Self> {
         Ok(command.delegate(tek, |command|Self::Device{command})?)
     }
-    fn message (&self, tek: &mut Tek, command: MessageCommand) -> Perhaps<Self> {
+    fn message (tek: &mut Tek, command: MessageCommand) -> Perhaps<Self> {
         Ok(command.delegate(tek, |command|Self::Message{command})?)
     }
-    fn color (&self, tek: &mut Tek, theme: ItemTheme) -> Perhaps<Self> {
+    fn color (tek: &mut Tek, theme: ItemTheme) -> Perhaps<Self> {
         Ok(tek.set_color(Some(theme)).map(|theme|Self::Color{theme}))
     }
-    fn enqueue (&self, tek: &mut Tek, clip: Option<Arc<RwLock<MidiClip>>>) -> Perhaps<Self> {
+    fn enqueue (tek: &mut Tek, clip: Option<Arc<RwLock<MidiClip>>>) -> Perhaps<Self> {
         todo!()
     }
-    fn history (&self, tek: &mut Tek, delta: isize) -> Perhaps<Self> {
+    fn history (tek: &mut Tek, delta: isize) -> Perhaps<Self> {
         todo!()
     }
-    fn zoom (&self, tek: &mut Tek, zoom: usize) -> Perhaps<Self> {
+    fn zoom (tek: &mut Tek, zoom: usize) -> Perhaps<Self> {
         todo!()
     }
-    fn launch (&self, tek: &mut Tek) -> Perhaps<Self> {
+    fn launch (tek: &mut Tek) -> Perhaps<Self> {
         tek.launch();
         Ok(None)
     }
-    fn select (&self, tek: &mut Tek, selection: Selection) -> Perhaps<Self> {
+    fn select (tek: &mut Tek, selection: Selection) -> Perhaps<Self> {
         tek.select(selection);
         Ok(None)
         //("select"  [t: usize, s: usize] Some(match (t.expect("no track"), s.expect("no scene")) {
@@ -348,129 +344,169 @@ impl TekCommand {
             //(0, s) => Self::Select(Selection::Scene(s)),
             //(t, s) => Self::Select(Selection::TrackClip { track: t, scene: s }) })))
     }
-    fn stop_all (&self, tek: &mut Tek) -> Perhaps<Self> {
+    fn stop_all (tek: &mut Tek) -> Perhaps<Self> {
         tek.stop_all();
         Ok(None)
     }
 }
 
-#[tengri_proc::command(Tek)]
-impl InputCommand {
-    fn add (&self, tek: &mut Tek) -> Perhaps<Self> {
+#[tengri_proc::command(Tek)] impl InputCommand {
+    fn add (tek: &mut Tek) -> Perhaps<Self> {
         tek.midi_in_add()?;
         Ok(None)
     }
 }
 
-#[tengri_proc::command(Tek)]
-impl OutputCommand {
-    fn add (&self, tek: &mut Tek) -> Perhaps<Self> {
+#[tengri_proc::command(Tek)] impl OutputCommand {
+    fn add (tek: &mut Tek) -> Perhaps<Self> {
         tek.midi_out_add()?;
         Ok(None)
     }
 }
 
-#[tengri_proc::command(Tek)]
-impl DeviceCommand {
-    fn picker (&self, tek: &mut Tek) -> Perhaps<Self> {
+#[tengri_proc::command(Tek)] impl DeviceCommand {
+    fn picker (tek: &mut Tek) -> Perhaps<Self> {
         tek.device_picker_show();
         Ok(None)
     }
-    fn pick (&self, tek: &mut Tek, i: usize) -> Perhaps<Self> {
+    fn pick (tek: &mut Tek, i: usize) -> Perhaps<Self> {
         tek.device_pick(i);
         Ok(None)
     }
-    fn add (&self, tek: &mut Tek, i: usize) -> Perhaps<Self> {
+    fn add (tek: &mut Tek, i: usize) -> Perhaps<Self> {
         tek.device_add(i);
         Ok(None)
     }
 }
 
-#[tengri_proc::command(Tek)]
-impl MessageCommand {
-    fn dismiss (&self, tek: &mut Tek) -> Perhaps<Self> {
+#[tengri_proc::command(Tek)] impl MessageCommand {
+    fn dismiss (tek: &mut Tek) -> Perhaps<Self> {
         tek.message_dismiss();
         Ok(None)
     }
 }
 
-#[tengri_proc::command(Tek)]
-impl TrackCommand {
-    //(TogglePlay []                       Some(Self::TogglePlay))
-    //(ToggleSolo []                       Some(Self::ToggleSolo))
-    //(SetSize    [t: usize]               cmd_todo!("\n\rtodo: {self:?}"))
-    //(SetZoom    [z: usize]               cmd_todo!("\n\rtodo: {self:?}"))
-    //(Swap       [a: usize, b: usize]     cmd_todo!("\n\rtodo: {self:?}"))
-    //(Del        [index: usize]           cmd!(app.track_del(index)))
-    //(Stop       [index: usize]           cmd!(app.tracks[index].player.enqueue_next(None)))
-    //(Add        []                       Some(Self::Del(app.track_add_focus()?)))
-    //(SetColor   [i: usize, c: ItemTheme] Some(Self::SetColor(i, app.track_set_color(i, c))))
-    //(ToggleRec  [] { app.track_toggle_record();  Some(Self::ToggleRec) })
-    //(ToggleMon  [] { app.track_toggle_monitor(); Some(Self::ToggleMon) }))
-        //("add"    []                   Some(Self::Add))
-        //("size"   [a: usize]           Some(Self::SetSize(a.unwrap())))
-        //("zoom"   [a: usize]           Some(Self::SetZoom(a.unwrap())))
-        //("color"  [a: usize]           Some(Self::SetColor(a.unwrap(), ItemTheme::random())))
-        //("delete" [a: Option<usize>]   Some(Self::Del(a.flatten().unwrap())))
-        //("stop"   [a: usize]           Some(Self::Stop(a.unwrap())))
-        //("swap"   [a: usize, b: usize] Some(Self::Swap(a.unwrap(), b.unwrap())))
-        //("play"   []                   Some(Self::TogglePlay))
-        //("solo"   []                   Some(Self::ToggleSolo))
-        //("rec"    []                   Some(Self::ToggleRec))
-        //("mon"    []                   Some(Self::ToggleMon))));
+#[tengri_proc::command(Tek)] impl TrackCommand {
+    fn toggle_play (tek: &mut Tek) -> Perhaps<Self> {
+        todo!()
+    }
+    fn toggle_solo (tek: &mut Tek) -> Perhaps<Self> {
+        todo!()
+    }
+    fn toggle_rec (tek: &mut Tek) -> Perhaps<Self> {
+        tek.track_toggle_record();
+        Ok(Some(Self::ToggleRec))
+    }
+    fn toggle_mon (tek: &mut Tek) -> Perhaps<Self> {
+        tek.track_toggle_monitor();
+        Ok(Some(Self::ToggleMon))
+    }
+    fn set_size (tek: &mut Tek, size: usize) -> Perhaps<Self> {
+        todo!()
+    }
+    fn set_zoom (tek: &mut Tek, zoom: usize) -> Perhaps<Self> {
+        todo!()
+    }
+    fn swap (tek: &mut Tek, index: usize, other: usize) -> Perhaps<Self> {
+        todo!();
+        Ok(Some(Self::Swap { index, other }))
+    }
+    fn del (tek: &mut Tek, index: usize) -> Perhaps<Self> {
+        tek.track_del(index);
+        Ok(None)
+    }
+    fn stop (tek: &mut Tek, index: usize) -> Perhaps<Self> {
+        tek.tracks[index].player.enqueue_next(None);
+        Ok(None)
+    }
+    fn add (tek: &mut Tek) -> Perhaps<Self> {
+        Ok(Some(Self::Del { index: tek.track_add_focus()? }))
+    }
+    fn set_color (tek: &mut Tek, index: usize, color: ItemTheme) -> Perhaps<Self> {
+        Ok(Some(Self::SetColor { index, color: tek.track_set_color(index, color) }))
+    }
 }
 
-#[tengri_proc::command(Tek)]
-impl SceneCommand {
-    //(Swap     [a: usize, b: usize]     cmd_todo!("\n\rtodo: {self:?}"))
-    //(SetSize  [index: usize]           cmd_todo!("\n\rtodo: {self:?}"))
-    //(SetZoom  [zoom: usize]            cmd_todo!("\n\rtodo: {self:?}"))
-    //(Enqueue  [scene: usize]           cmd!(app.scene_enqueue(scene)))
-    //(Del      [index: usize]           cmd!(app.scene_del(index)))
-    //(Add      []                       Some(Self::Del(app.scene_add_focus()?)))
-    //(SetColor [i: usize, c: ItemTheme] Some(Self::SetColor(i, app.scene_set_color(i, c)))))
-        //("add"     []                   Some(Self::Add))
-        //("delete"  [a: Option<usize>]   Some(Self::Del(a.flatten().unwrap())))
-        //("zoom"    [a: usize]           Some(Self::SetZoom(a.unwrap())))
-        //("color"   [a: usize]           Some(Self::SetColor(a.unwrap(), ItemTheme::G[128])))
-        //("enqueue" [a: usize]           Some(Self::Enqueue(a.unwrap())))
-        //("swap"    [a: usize, b: usize] Some(Self::Swap(a.unwrap(), b.unwrap()))))
+#[tengri_proc::command(Tek)] impl SceneCommand {
+    fn add (tek: &mut Tek) -> Perhaps<Self> {
+        todo!()
+    }
+    fn del (tek: &mut Tek, index: usize) -> Perhaps<Self> {
+        tek.scene_del(index);
+        Ok(None)
+    }
+    fn enqueue (tek: &mut Tek, index: usize) -> Perhaps<Self> {
+        tek.scene_enqueue(index);
+        Ok(None)
+    }
+    fn set_color (tek: &mut Tek, index: usize, color: ItemTheme) -> Perhaps<Self> {
+        Ok(Some(Self::SetColor { index, color: tek.scene_set_color(index, color) }))
+    }
+    fn set_size (tek: &mut Tek, index: usize, size: usize) -> Perhaps<Self> {
+        todo!()
+    }
+    fn set_zoom (tek: &mut Tek, index: usize, zoom: usize) -> Perhaps<Self> {
+        todo!()
+    }
+    fn swap (tek: &mut Tek, index: usize, other: usize) -> Perhaps<Self> {
+        todo!();
+        Ok(Some(Self::Swap { index, other }))
+    }
 }
 
-#[tengri_proc::command(Tek)]
-impl ClipCommand {
-    //(Get      [a: usize, b: usize]          cmd_todo!("\n\rtodo: clip: get: {a} {b}"))
-    //(Edit     [clip: MaybeClip]             cmd_todo!("\n\rtodo: clip: edit: {clip:?}"))
-    //(SetLoop  [t: usize, s: usize, l: bool] cmd_todo!("\n\rtodo: {self:?}"))
-    //(Put      [t: usize, s: usize, c: MaybeClip]
-        //Some(Self::Put(t, s, app.clip_put(t, s, c))))
-    //(Enqueue  [t: usize, s: usize]
-        //cmd!(app.tracks[t].player.enqueue_next(app.scenes[s].clips[t].as_ref())))
-    //(SetColor [t: usize, s: usize, c: ItemTheme]
-        //app.clip_set_color(t, s, c).map(|o|Self::SetColor(t, s, o)))));
-        //("edit"    [a: MaybeClip] Some(Self::Edit(a.unwrap())))
-        //("color"   [a: usize, b: usize] Some(Self::SetColor(a.unwrap(), b.unwrap(), ItemTheme::random())))
-        //("enqueue" [a: usize, b: usize] Some(Self::Enqueue(a.unwrap(), b.unwrap())))
-        //("get"     [a: usize, b: usize] Some(Self::Get(a.unwrap(), b.unwrap())))
-        //("loop"    [a: usize, b: usize, c: bool] Some(Self::SetLoop(a.unwrap(), b.unwrap(), c.unwrap())))
-        //("put"     [a: usize, b: usize, c: MaybeClip] Some(Self::Put(a.unwrap(), b.unwrap(), c.unwrap())))
+#[tengri_proc::command(Tek)] impl ClipCommand {
+    fn get (tek: &mut Tek, a: usize, b: usize) -> Perhaps<Self> {
+        //(Get      [a: usize, b: usize]          cmd_todo!("\n\rtodo: clip: get: {a} {b}"))
+            //("get"     [a: usize, b: usize] Some(Self::Get(a.unwrap(), b.unwrap())))
+        todo!()
+    }
+    fn edit (tek: &mut Tek, a: usize, b: usize) -> Perhaps<Self> {
+        //(Edit     [clip: MaybeClip]             cmd_todo!("\n\rtodo: clip: edit: {clip:?}"))
+            //("edit"    [a: MaybeClip] Some(Self::Edit(a.unwrap())))
+        todo!()
+    }
+    fn set_loop (tek: &mut Tek, a: usize, b: usize) -> Perhaps<Self> {
+        //(SetLoop  [t: usize, s: usize, l: bool] cmd_todo!("\n\rtodo: {self:?}"))
+            //("loop"    [a: usize, b: usize, c: bool] Some(Self::SetLoop(a.unwrap(), b.unwrap(), c.unwrap())))
+        todo!()
+    }
+    fn put (tek: &mut Tek, a: usize, b: usize) -> Perhaps<Self> {
+        //(Put      [t: usize, s: usize, c: MaybeClip]
+            //Some(Self::Put(t, s, app.clip_put(t, s, c))))
+            //("put"     [a: usize, b: usize, c: MaybeClip] Some(Self::Put(a.unwrap(), b.unwrap(), c.unwrap())))
+        todo!()
+    }
+    fn del (tek: &mut Tek, a: usize, b: usize) -> Perhaps<Self> {
         //("delete"  [a: usize, b: usize] Some(Self::Put(a.unwrap(), b.unwrap(), None))))
+        todo!()
+    }
+    fn enqueue (tek: &mut Tek, a: usize, b: usize) -> Perhaps<Self> {
+        //(Enqueue  [t: usize, s: usize]
+            //cmd!(app.tracks[t].player.enqueue_next(app.scenes[s].clips[t].as_ref())))
+            //("enqueue" [a: usize, b: usize] Some(Self::Enqueue(a.unwrap(), b.unwrap())))
+        todo!()
+    }
+   fn set_color (tek: &mut Tek, a: usize, b: usize) -> Perhaps<Self> {
+        //(SetColor [t: usize, s: usize, c: ItemTheme]
+            //app.clip_set_color(t, s, c).map(|o|Self::SetColor(t, s, o)))));
+            //("color"   [a: usize, b: usize] Some(Self::SetColor(a.unwrap(), b.unwrap(), ItemTheme::random())))
+        todo!()
+    }
 }
 
-#[tengri_proc::command(MidiPool)]
-impl PoolCommand {
+#[tengri_proc::command(MidiPool)] impl PoolCommand {
     /// Toggle visibility of pool
-    fn show   (&self, pool: &mut MidiPool, visible: bool) -> Perhaps<Self> {
+    fn show (pool: &mut MidiPool, visible: bool) -> Perhaps<Self> {
         pool.visible = visible;
-        Ok(Some(Self::Show(!visible)))
+        Ok(Some(Self::Show { visible: !visible }))
     }
     /// Select a clip from the clip pool
-    fn select (&self, pool: &mut MidiPool, index: usize) -> Perhaps<Self> {
+    fn select (pool: &mut MidiPool, index: usize) -> Perhaps<Self> {
         pool.set_clip_index(index);
         Ok(None)
     }
     /// Rename a clip
-    fn rename (&self, pool: &mut MidiPool, command: ClipRenameCommand) -> Perhaps<Self> {
+    fn rename (pool: &mut MidiPool, command: ClipRenameCommand) -> Perhaps<Self> {
         Ok(match command {
             ClipRenameCommand::Begin => {
                 pool.begin_clip_rename();
@@ -480,7 +516,7 @@ impl PoolCommand {
         })
     }
     /// Change the length of a clip
-    fn length (&self, pool: &mut MidiPool, command: ClipLengthCommand) -> Perhaps<Self> {
+    fn length (pool: &mut MidiPool, command: ClipLengthCommand) -> Perhaps<Self> {
         Ok(match command {
             ClipLengthCommand::Begin => {
                 pool.begin_clip_length();
@@ -490,9 +526,9 @@ impl PoolCommand {
         })
     }
     /// Import from file
-    fn import (&self, pool: &mut MidiPool, command: FileBrowserCommand) -> Perhaps<Self> {
+    fn import (pool: &mut MidiPool, command: FileBrowserCommand) -> Perhaps<Self> {
         Ok(match command {
-            ClipImportCommand::Begin => {
+            FileBrowserCommand::Begin => {
                 pool.begin_import();
                 None
             },
@@ -500,9 +536,9 @@ impl PoolCommand {
         })
     }
     /// Export to file
-    fn export (&self, pool: &mut MidiPool, command: FileBrowserCommand) -> Perhaps<Self> {
+    fn export (pool: &mut MidiPool, command: FileBrowserCommand) -> Perhaps<Self> {
         Ok(match command {
-            ClipExportCommand::Begin => {
+            FileBrowserCommand::Begin => {
                 pool.begin_export();
                 None
             },
@@ -510,14 +546,13 @@ impl PoolCommand {
         })
     }
     /// Update the contents of the clip pool
-    fn clip (&self, pool: &mut MidiPool, command: PoolClipCommand) -> Perhaps<Self> {
-        command.execute(pool)?.map(|command|Self::Clip{command})
+    fn clip (pool: &mut MidiPool, command: PoolClipCommand) -> Perhaps<Self> {
+        Ok(command.execute(pool)?.map(|command|Self::Clip{command}))
     }
 }
 
-#[tengri_proc::command(MidiPool)]
-impl PoolClipCommand {
-    fn add (&self, pool: &mut MidiPool, index: usize, clip: MidiClip) -> Perhaps<Self> {
+#[tengri_proc::command(MidiPool)] impl PoolClipCommand {
+    fn add (pool: &mut MidiPool, index: usize, clip: MidiClip) -> Perhaps<Self> {
         let mut index = index;
         let clip = Arc::new(RwLock::new(clip));
         let mut clips = pool.clips_mut();
@@ -527,17 +562,17 @@ impl PoolClipCommand {
         } else {
             clips.insert(index, clip);
         }
-        Ok(Some(Self::Delete(index)))
+        Ok(Some(Self::Delete { index }))
     }
-    fn delete (&self, pool: &mut MidiPool, index: usize) -> Perhaps<Self> {
+    fn delete (pool: &mut MidiPool, index: usize) -> Perhaps<Self> {
         let clip = pool.clips_mut().remove(index).read().unwrap().clone();
-        Ok(Some(Self::Add(index, clip)))
+        Ok(Some(Self::Add { index, clip }))
     }
-    fn swap (&self, pool: &mut MidiPool, index: usize, other: usize) -> Perhaps<Self> {
+    fn swap (pool: &mut MidiPool, index: usize, other: usize) -> Perhaps<Self> {
         pool.clips_mut().swap(index, other);
-        Ok(Some(Self::Swap(index, other)))
+        Ok(Some(Self::Swap { index, other }))
     }
-    fn import (&self, pool: &mut MidiPool, index: usize, path: PathBuf) -> Perhaps<Self> {
+    fn import (pool: &mut MidiPool, index: usize, path: PathBuf) -> Perhaps<Self> {
         let bytes = std::fs::read(&path)?;
         let smf = Smf::parse(bytes.as_slice())?;
         let mut t = 0u32;
@@ -554,50 +589,49 @@ impl PoolClipCommand {
         for event in events.iter() {
             clip.notes[event.0 as usize].push(event.2);
         }
-        Self::Add(index, clip).execute(pool)?
+        Ok(Self::Add { index, clip }.execute(pool)?)
     }
-    fn export (&self, pool: &mut MidiPool, index: usize, path: PathBuf) -> Perhaps<Self> {
+    fn export (pool: &mut MidiPool, index: usize, path: PathBuf) -> Perhaps<Self> {
         todo!("export clip to midi file");
     }
-    fn set_name (&self, pool: &mut MidiPool, index: usize, name: Arc<str>) -> Perhaps<Self> {
+    fn set_name (pool: &mut MidiPool, index: usize, name: Arc<str>) -> Perhaps<Self> {
         let clip = &mut pool.clips_mut()[index];
         let old_name = clip.read().unwrap().name.clone();
         clip.write().unwrap().name = name;
-        Ok(Some(Self::SetName(index, old_name)))
+        Ok(Some(Self::SetName { index, name: old_name }))
     }
-    fn set_length (&self, pool: &mut MidiPool, index: usize, length: usize) -> Perhaps<Self> {
+    fn set_length (pool: &mut MidiPool, index: usize, length: usize) -> Perhaps<Self> {
         let clip = &mut pool.clips_mut()[index];
         let old_len = clip.read().unwrap().length;
         clip.write().unwrap().length = length;
-        Ok(Some(Self::SetLength(index, old_len)))
+        Ok(Some(Self::SetLength { index, length: old_len }))
     }
-    fn set_color (&self, pool: &mut MidiPool, index: usize, color: ItemColor) -> Perhaps<Self> {
+    fn set_color (pool: &mut MidiPool, index: usize, color: ItemColor) -> Perhaps<Self> {
         let mut color = ItemTheme::from(color);
         std::mem::swap(&mut color, &mut pool.clips()[index].write().unwrap().color);
-        Ok(Some(Self::SetColor(index, color.base)))
+        Ok(Some(Self::SetColor { index, color: color.base }))
     }
 }
 
-#[tengri_proc::command(MidiPool)]
-impl ClipRenameCommand {
-    fn begin (&self, pool: &mut MidiPool) -> Perhaps<Self> {
+#[tengri_proc::command(MidiPool)] impl ClipRenameCommand {
+    fn begin (pool: &mut MidiPool) -> Perhaps<Self> {
         unreachable!();
     }
-    fn cancel (&self, pool: &mut MidiPool) -> Perhaps<Self> {
+    fn cancel (pool: &mut MidiPool) -> Perhaps<Self> {
         if let Some(PoolMode::Rename(clip, ref mut old_name)) = pool.mode_mut().clone() {
             pool.clips()[clip].write().unwrap().name = old_name.clone().into();
         }
         return Ok(None)
     }
-    fn confirm (&self, pool: &mut MidiPool) -> Perhaps<Self> {
+    fn confirm (pool: &mut MidiPool) -> Perhaps<Self> {
         if let Some(PoolMode::Rename(clip, ref mut old_name)) = pool.mode_mut().clone() {
             let old_name = old_name.clone();
-            pool.mode_mut() = None;
-            return Ok(Some(Self::Set(old_name)))
+            *pool.mode_mut() = None;
+            return Ok(Some(Self::Set { value: old_name }))
         }
         return Ok(None)
     }
-    fn set (&self, pool: &mut MidiPool, value: Arc<str>) -> Perhaps<Self> {
+    fn set (pool: &mut MidiPool, value: Arc<str>) -> Perhaps<Self> {
         if let Some(PoolMode::Rename(clip, ref mut old_name)) = pool.mode_mut().clone() {
             pool.clips()[clip].write().unwrap().name = value;
         }
@@ -605,18 +639,17 @@ impl ClipRenameCommand {
     }
 }
 
-#[tengri_proc::command(MidiPool)]
-impl ClipLengthCommand {
-    fn begin (&self, pool: &mut MidiPool) -> Perhaps<Self> {
+#[tengri_proc::command(MidiPool)] impl ClipLengthCommand {
+    fn begin (pool: &mut MidiPool) -> Perhaps<Self> {
         unreachable!()
     }
-    fn cancel (&self, pool: &mut MidiPool) -> Perhaps<Self> {
+    fn cancel (pool: &mut MidiPool) -> Perhaps<Self> {
         if let Some(PoolMode::Length(..)) = pool.mode_mut().clone() {
             *pool.mode_mut() = None;
         }
         Ok(None)
     }
-    fn set (&self, pool: &mut MidiPool, length: usize) -> Perhaps<Self> {
+    fn set (pool: &mut MidiPool, length: usize) -> Perhaps<Self> {
         if let Some(PoolMode::Length(clip, ref mut length, ref mut focus))
             = pool.mode_mut().clone()
         {
@@ -624,14 +657,14 @@ impl ClipLengthCommand {
             {
                 let clip = pool.clips()[clip].clone();//.write().unwrap();
                 old_length = Some(clip.read().unwrap().length);
-                clip.write().unwrap().length = length;
+                clip.write().unwrap().length = *length;
             }
-            pool.mode_mut() = None;
+            *pool.mode_mut() = None;
             return Ok(old_length.map(|length|Self::Set { length }))
         }
         Ok(None)
     }
-    fn next (&self, pool: &mut MidiPool) -> Perhaps<Self> {
+    fn next (pool: &mut MidiPool) -> Perhaps<Self> {
         if let Some(PoolMode::Length(clip, ref mut length, ref mut focus))
             = pool.mode_mut().clone()
         {
@@ -639,7 +672,7 @@ impl ClipLengthCommand {
         }
         Ok(None)
     }
-    fn prev (&self, pool: &mut MidiPool) -> Perhaps<Self> {
+    fn prev (pool: &mut MidiPool) -> Perhaps<Self> {
         if let Some(PoolMode::Length(clip, ref mut length, ref mut focus))
             = pool.mode_mut().clone()
         {
@@ -647,102 +680,110 @@ impl ClipLengthCommand {
         }
         Ok(None)
     }
-    fn inc (&self, pool: &mut MidiPool) -> Perhaps<Self> {
+    fn inc (pool: &mut MidiPool) -> Perhaps<Self> {
         if let Some(PoolMode::Length(clip, ref mut length, ref mut focus))
             = pool.mode_mut().clone()
         {
             match focus {
-                Bar  => { *length += 4 * PPQ },
-                Beat => { *length += PPQ     },
-                Tick => { *length += 1       },
+                ClipLengthFocus::Bar  => { *length += 4 * PPQ },
+                ClipLengthFocus::Beat => { *length += PPQ     },
+                ClipLengthFocus::Tick => { *length += 1       },
             }
         }
         Ok(None)
     }
-    fn dec (&self, pool: &mut MidiPool) -> Perhaps<Self> {
-        if let Some(
-            PoolMode::Length(clip, ref mut length, ref mut focus)
-        ) = pool.mode_mut().clone() {
+    fn dec (pool: &mut MidiPool) -> Perhaps<Self> {
+        if let Some(PoolMode::Length(clip, ref mut length, ref mut focus))
+            = pool.mode_mut().clone()
+        {
             match focus {
-                Bar  => { *length = length.saturating_sub(4 * PPQ) },
-                Beat => { *length = length.saturating_sub(PPQ)     },
-                Tick => { *length = length.saturating_sub(1)       },
+                ClipLengthFocus::Bar  => { *length = length.saturating_sub(4 * PPQ) },
+                ClipLengthFocus::Beat => { *length = length.saturating_sub(PPQ)     },
+                ClipLengthFocus::Tick => { *length = length.saturating_sub(1)       },
             }
         }
         Ok(None)
     }
 }
 
-#[tengri_proc::command(MidiPool)]
-impl FileBrowserCommand {
-    fn begin (&self, pool: &mut MidiPool) -> Perhaps<Self> {
+#[tengri_proc::command(MidiPool)] impl FileBrowserCommand {
+    fn begin (pool: &mut MidiPool) -> Perhaps<Self> {
         unreachable!();
     }
-    fn cancel (&self, pool: &mut MidiPool) -> Perhaps<Self> {
+    fn cancel (pool: &mut MidiPool) -> Perhaps<Self> {
         pool.mode = None;
         Ok(None)
     }
-    fn confirm (&self, pool: &mut MidiPool) -> Perhaps<Self> {
+    fn confirm (pool: &mut MidiPool) -> Perhaps<Self> {
         Ok(match pool.mode {
             Some(PoolMode::Import(index, ref mut browser)) => {
                 if browser.is_file() {
-                    let index = *index;
                     let path = browser.path();
                     pool.mode = None;
-                    PoolClipCommand::Import(index, path).execute(pool)?;
+                    let _undo = PoolClipCommand::import(pool, index, path)?;
+                    None
                 } else if browser.is_dir() {
-                    pool.mode = Some(PoolMode::Import(*index, browser.chdir()?));
+                    pool.mode = Some(PoolMode::Import(index, browser.chdir()?));
+                    None
+                } else {
+                    None
                 }
             },
-            Some(PoolMode::Export(index, ref mut browser)) => match self {
-                Cancel => { pool.mode = None; },
-                _ => unreachable!()
+            Some(PoolMode::Export(index, ref mut browser)) => {
+                todo!()
             },
             _ => unreachable!(),
         })
     }
-    fn select (&self, pool: &mut MidiPool, index: usize) -> Perhaps<Self> {
-        Ok(match pool.mode {
-            Some(PoolMode::Import(index, ref mut browser)) => { browser.index = index; },
-            Some(PoolMode::Export(index, ref mut browser)) => { browser.index = index; },
-            _ => unreachable!(),
-        })
-    }
-    fn chdir (&self, pool: &mut MidiPool, dir: PathBuf) -> Perhaps<Self> {
+    fn select (pool: &mut MidiPool, index: usize) -> Perhaps<Self> {
         Ok(match pool.mode {
             Some(PoolMode::Import(index, ref mut browser)) => {
-                pool.mode = Some(PoolMode::Import(*index, FileBrowser::new(Some(dir))?));
+                browser.index = index;
+                None
             },
             Some(PoolMode::Export(index, ref mut browser)) => {
-                pool.mode = Some(PoolMode::Export(*index, FileBrowser::new(Some(dir))?));
+                browser.index = index;
+                None
             },
             _ => unreachable!(),
         })
     }
-    fn filter (&self, pool: &mut MidiPool, filter: Arc<str>) -> Perhaps<Self> {
+    fn chdir (pool: &mut MidiPool, dir: PathBuf) -> Perhaps<Self> {
+        Ok(match pool.mode {
+            Some(PoolMode::Import(index, ref mut browser)) => {
+                pool.mode = Some(PoolMode::Import(index, FileBrowser::new(Some(dir))?));
+                None
+            },
+            Some(PoolMode::Export(index, ref mut browser)) => {
+                pool.mode = Some(PoolMode::Export(index, FileBrowser::new(Some(dir))?));
+                None
+            },
+            _ => unreachable!(),
+        })
+    }
+    fn filter (pool: &mut MidiPool, filter: Arc<str>) -> Perhaps<Self> {
         todo!()
     }
 }
 
-#[tengri_proc::command(MidiEditor)]
-impl MidiEditCommand {
+#[tengri_proc::command(MidiEditor)] impl MidiEditCommand {
     // TODO: 1-9 seek markers that by default start every 8th of the clip
-    fn note_append (&self, editor: &mut MidiEditor) -> Perhaps<Self> {
+    fn note_append (editor: &mut MidiEditor) -> Perhaps<Self> {
         editor.put_note(true);
         Ok(None)
     }
-    fn note_put (&self, editor: &mut MidiEditor) -> Perhaps<Self> {
+    fn note_put (editor: &mut MidiEditor) -> Perhaps<Self> {
         editor.put_note(false);
         Ok(None)
     }
-    fn note_del (&self, editor: &mut MidiEditor) -> Perhaps<Self> {
+    fn note_del (editor: &mut MidiEditor) -> Perhaps<Self> {
         todo!()
     }
-    fn note_pos (&self, editor: &mut MidiEditor, pos: usize) -> Perhaps<Self> {
+    fn note_pos (editor: &mut MidiEditor, pos: usize) -> Perhaps<Self> {
         editor.set_note_pos(pos.min(127));
         Ok(None)
     }
-    fn note_len (&self, editor: &mut MidiEditor, value: usize) -> Perhaps<Self> {
+    fn note_len (editor: &mut MidiEditor, value: usize) -> Perhaps<Self> {
         //let note_len = editor.get_note_len();
         //let time_zoom = editor.get_time_zoom();
         editor.set_note_len(value);
@@ -751,28 +792,28 @@ impl MidiEditCommand {
         //}
         Ok(None)
     }
-    fn note_scroll (&self, editor: &mut MidiEditor, value: usize) {
+    fn note_scroll (editor: &mut MidiEditor, value: usize) -> Perhaps<Self> {
         editor.set_note_lo(value.min(127));
         Ok(None)
     }
-    fn time_pos (&self, editor: &mut MidiEditor, value: usize) -> Perhaps<Self> {
+    fn time_pos (editor: &mut MidiEditor, value: usize) -> Perhaps<Self> {
         editor.set_time_pos(value);
         Ok(None)
     }
-    fn time_scroll (&self, editor: &mut MidiEditor, value: usize) -> Perhaps<Self> {
+    fn time_scroll (editor: &mut MidiEditor, value: usize) -> Perhaps<Self> {
         editor.set_time_start(value);
         Ok(None)
     }
-    fn time_zoom (&self, editor: &mut MidiEditor, value: usize) -> Perhaps<Self> {
-        editor.time_zoom().set(value);
+    fn time_zoom (editor: &mut MidiEditor, value: usize) -> Perhaps<Self> {
+        editor.set_time_zoom(value);
         editor.redraw();
         Ok(None)
     }
-    fn time_lock (&self, editor: &mut MidiEditor, value: bool) -> Perhaps<Self> {
+    fn time_lock (editor: &mut MidiEditor, value: bool) -> Perhaps<Self> {
         editor.set_time_lock(value);
         Ok(None)
     }
-    fn show (&self, editor: &mut MidiEditor, clip: Option<Arc<RwLock<MidiClip>>>) -> Perhaps<Self> {
+    fn show (editor: &mut MidiEditor, clip: Option<Arc<RwLock<MidiClip>>>) -> Perhaps<Self> {
         editor.set_clip(clip.as_ref());
         Ok(None)
     }
diff --git a/crates/app/src/model/editor.rs b/crates/app/src/model/editor.rs
index 9a9d5836..fec878b1 100644
--- a/crates/app/src/model/editor.rs
+++ b/crates/app/src/model/editor.rs
@@ -53,9 +53,9 @@ impl MidiEditor {
         let mut redraw = false;
         if let Some(clip) = self.clip() {
             let mut clip   = clip.write().unwrap();
-            let note_start = self.time_pos();
-            let note_pos   = self.note_pos();
-            let note_len   = self.note_len();
+            let note_start = self.get_time_pos();
+            let note_pos   = self.get_note_pos();
+            let note_len   = self.get_note_len();
             let note_end   = note_start + (note_len.saturating_sub(1));
             let key: u7    = u7::from(note_pos as u8);
             let vel: u7    = 100.into();
diff --git a/crates/app/src/view.rs b/crates/app/src/view.rs
index d1377bee..2f1bfdd9 100644
--- a/crates/app/src/view.rs
+++ b/crates/app/src/view.rs
@@ -1195,8 +1195,8 @@ impl MidiViewer for PianoHorizontal {
             let clip       = clip.read().unwrap();
             let buf_size   = self.buffer_size(&clip);
             let mut buffer = BigBuffer::from(buf_size);
-            let note_len   = self.note_len();
-            let time_zoom  = self.time_zoom().get();
+            let note_len   = self.get_note_len();
+            let time_zoom  = self.get_time_zoom();
             self.time_len().set(clip.length);
             PianoHorizontal::draw_bg(&mut buffer, &clip, time_zoom, note_len);
             PianoHorizontal::draw_fg(&mut buffer, &clip, time_zoom);
diff --git a/crates/device/src/clock/clock_api.rs b/crates/device/src/clock/clock_api.rs
index 097867fc..6faceb11 100644
--- a/crates/device/src/clock/clock_api.rs
+++ b/crates/device/src/clock/clock_api.rs
@@ -12,15 +12,15 @@ impl<T: HasClock> Command<T> for ClockCommand {
 
 #[tengri_proc::command(Clock)]
 impl ClockCommand {
-    fn play (self, state: &mut Clock, position: Option<u32>) -> Perhaps<Self> {
+    fn play (state: &mut Clock, position: Option<u32>) -> Perhaps<Self> {
         state.play_from(position)?;
         Ok(None) // TODO Some(Pause(previousPosition))
     }
-    fn pause (self, state: &mut Clock, position: Option<u32>) -> Perhaps<Self> {
+    fn pause (state: &mut Clock, position: Option<u32>) -> Perhaps<Self> {
         state.pause_at(position)?;
         Ok(None)
     }
-    fn toggle_playback (self, state: &mut Clock, position: Option<u32>) -> Perhaps<Self> {
+    fn toggle_playback (state: &mut Clock, position: Option<u32>) -> Perhaps<Self> {
         if state.is_rolling() {
             state.pause_at(position)?;
         } else {
@@ -28,25 +28,25 @@ impl ClockCommand {
         }
         Ok(None)
     }
-    fn seek_usec (self, state: &mut Clock, usec: f64) -> Perhaps<Self> {
+    fn seek_usec (state: &mut Clock, usec: f64) -> Perhaps<Self> {
         state.playhead.update_from_usec(usec);
         Ok(None)
     }
-    fn seek_sample (self, state: &mut Clock, sample: f64) -> Perhaps<Self> {
+    fn seek_sample (state: &mut Clock, sample: f64) -> Perhaps<Self> {
         state.playhead.update_from_sample(sample);
         Ok(None)
     }
-    fn seek_pulse (self, state: &mut Clock, pulse: f64) -> Perhaps<Self> {
+    fn seek_pulse (state: &mut Clock, pulse: f64) -> Perhaps<Self> {
         state.playhead.update_from_pulse(pulse);
         Ok(None)
     }
-    fn set_bpm (self, state: &mut Clock, bpm: f64) -> Perhaps<Self> {
+    fn set_bpm (state: &mut Clock, bpm: f64) -> Perhaps<Self> {
         Ok(Some(Self::SetBpm { bpm: state.timebase().bpm.set(bpm) }))
     }
-    fn set_quant (self, state: &mut Clock, quant: f64) -> Perhaps<Self> {
+    fn set_quant (state: &mut Clock, quant: f64) -> Perhaps<Self> {
         Ok(Some(Self::SetQuant { quant: state.quant.set(quant) }))
     }
-    fn set_sync (self, state: &mut Clock, sync: f64) -> Perhaps<Self> {
+    fn set_sync (state: &mut Clock, sync: f64) -> Perhaps<Self> {
         Ok(Some(Self::SetSync { sync: state.sync.set(sync) }))
     }
 }
diff --git a/crates/engine/src/note/note_range.rs b/crates/engine/src/note/note_range.rs
index 6804bd7a..40e7acc0 100644
--- a/crates/engine/src/note/note_range.rs
+++ b/crates/engine/src/note/note_range.rs
@@ -37,14 +37,23 @@ pub trait TimeRange {
     fn get_time_zoom (&self) -> usize {
         self.time_zoom().load(Ordering::Relaxed)
     }
+    fn set_time_zoom (&self, value: usize) -> usize {
+        self.time_zoom().swap(value, Ordering::Relaxed)
+    }
     fn time_lock (&self) -> &AtomicBool;
     fn get_time_lock (&self) -> bool {
         self.time_lock().load(Ordering::Relaxed)
     }
+    fn set_time_lock (&self, value: bool) -> bool {
+        self.time_lock().swap(value, Ordering::Relaxed)
+    }
     fn time_start (&self) -> &AtomicUsize;
     fn get_time_start (&self) -> usize {
         self.time_start().load(Ordering::Relaxed)
     }
+    fn set_time_start (&self, value: usize) -> usize {
+        self.time_start().swap(value, Ordering::Relaxed)
+    }
     fn time_axis (&self) -> &AtomicUsize;
     fn get_time_axis (&self) -> usize {
         self.time_axis().load(Ordering::Relaxed)
diff --git a/deps/tengri b/deps/tengri
index 2a6087e1..a16603fb 160000
--- a/deps/tengri
+++ b/deps/tengri
@@ -1 +1 @@
-Subproject commit 2a6087e1c7086f09b1ade22c84ff62642df7c723
+Subproject commit a16603fbc88a41c0cb4a315383cb647b0f9bb2b5