diff --git a/backends/x/entity.go b/backends/x/entity.go
index 6252d55..78053f3 100644
--- a/backends/x/entity.go
+++ b/backends/x/entity.go
@@ -10,18 +10,25 @@ type entity struct {
 	children    []*entity
 	element     tomo.Element
 	
-	drawDirty   bool
-	layoutDirty bool
-	
-	bounds      image.Rectangle
-	minWidth    int
-	minHeight   int
+	bounds        image.Rectangle
+	clippedBounds image.Rectangle
+	minWidth      int
+	minHeight     int
+
+	layoutInvalid bool
+	isContainer   bool
 }
 
-func bind (element tomo.Element) *entity {
-	entity := &entity { drawDirty: true }
+func bind (parent *entity, window *window, element tomo.Element) *entity {
+	entity := &entity {
+		window:  window,
+		parent:  parent,
+		element: element,
+	}
+	entity.Invalidate()
 	if _, ok := element.(tomo.Container); ok {
-		entity.layoutDirty = true
+		entity.isContainer = true
+		entity.InvalidateLayout()
 	}
 
 	element.Bind(entity)
@@ -38,7 +45,8 @@ func (entity *entity) unbind () {
 // ----------- Entity ----------- //
 
 func (entity *entity) Invalidate () {
-	entity.drawDirty = true
+	if entity.window.system.invalidateIgnore { return }
+	entity.window.drawingInvalid.Add(entity)
 }
 
 func (entity *entity) Bounds () image.Rectangle {
@@ -64,18 +72,20 @@ func (entity *entity) DrawBackground (destination canvas.Canvas, bounds image.Re
 // ----------- ContainerEntity ----------- //
 
 func (entity *entity) InvalidateLayout () {
-	entity.layoutDirty = true
+	if !entity.isContainer { return }
+	entity.layoutInvalid = true
+	entity.window.system.anyLayoutInvalid = true
 }
 
 func (entity *entity) Adopt (child tomo.Element) {
-	entity.children = append(entity.children, bind(child))
+	entity.children = append(entity.children, bind(entity, entity.window, child))
 }
 
 func (entity *entity) Insert (index int, child tomo.Element) {
 	entity.children = append (
 		entity.children[:index + 1],
 		entity.children[index:]...)
-	entity.children[index] = bind(child)
+	entity.children[index] = bind(entity, entity.window, child)
 }
 
 func (entity *entity) Disown (index int) {
@@ -104,7 +114,13 @@ func (entity *entity) CountChildren () int {
 }
 
 func (entity *entity) PlaceChild (index int, bounds image.Rectangle) {
-	entity.children[index].bounds = bounds
+	child := entity.children[index]
+	child.bounds = bounds
+	child.clippedBounds = entity.bounds.Intersect(bounds)
+	child.Invalidate()
+	if child.isContainer {
+		child.InvalidateLayout()
+	}
 }
 
 func (entity *entity) ChildMinimumSize (index int) (width, height int) {
diff --git a/backends/x/event.go b/backends/x/event.go
index 4675c2f..a796bb1 100644
--- a/backends/x/event.go
+++ b/backends/x/event.go
@@ -41,7 +41,6 @@ func (sum *scrollSum) add (button xproto.Button, window *window, state uint16) {
 			sum.x += scrollDistance
 		}
 	}
-
 }
 
 func (window *window) handleExpose (
@@ -49,6 +48,7 @@ func (window *window) handleExpose (
 	event xevent.ExposeEvent,
 ) {
 	_, region := window.compressExpose(*event.ExposeEvent)
+	window.system.afterEvent()
 	window.pushRegion(region)
 }
 
@@ -74,7 +74,6 @@ func (window *window) handleConfigureNotify (
 	window.updateBounds (
 		configureEvent.X, configureEvent.Y,
 		configureEvent.Width, configureEvent.Height)
-	
 
 	if sizeChanged {
 		configureEvent = window.compressConfigureNotify(configureEvent)
@@ -85,8 +84,11 @@ func (window *window) handleConfigureNotify (
 		window.resizeChildToFit()
 
 		if !window.exposeEventFollows(configureEvent) {
-			window.redrawChildEntirely()
+			window.child.Invalidate()
+			window.child.InvalidateLayout()
 		}
+		
+		window.system.afterEvent()
 	}
 }
 
@@ -136,21 +138,21 @@ func (window *window) handleKeyPress (
 	modifiers.NumberPad = numberPad
 
 	if key == input.KeyTab && modifiers.Alt {
-		if child, ok := window.child.(tomo.Focusable); ok {
-			direction := input.KeynavDirectionForward
-			if modifiers.Shift {
-				direction = input.KeynavDirectionBackward
-			}
-
-			if !child.HandleFocus(direction) {
-				child.HandleUnfocus()
-			}
-		}
+		// if child, ok := window.child.element.(tomo.Focusable); ok {
+			// direction := input.KeynavDirectionForward
+			// if modifiers.Shift {
+				// direction = input.KeynavDirectionBackward
+			// }
+// 
+			// // TODO
+		// }
 	} else if key == input.KeyEscape && window.shy {
 		window.Close()
-	} else if child, ok := window.child.(tomo.KeyboardTarget); ok {
+	} else if child, ok := window.child.element.(tomo.KeyboardTarget); ok {
 		child.HandleKeyDown(key, modifiers)
 	}
+	
+	window.system.afterEvent()
 }
 
 func (window *window) handleKeyRelease (
@@ -182,9 +184,11 @@ func (window *window) handleKeyRelease (
 	modifiers := window.modifiersFromState(keyEvent.State)
 	modifiers.NumberPad = numberPad
 	
-	if child, ok := window.child.(tomo.KeyboardTarget); ok {
+	if child, ok := window.child.element.(tomo.KeyboardTarget); ok {
 		child.HandleKeyUp(key, modifiers)
 	}
+	
+	window.system.afterEvent()
 }
 
 func (window *window) handleButtonPress (
@@ -205,7 +209,7 @@ func (window *window) handleButtonPress (
 	if !insideWindow && window.shy && !scrolling {
 		window.Close()
 	} else if scrolling {
-		if child, ok := window.child.(tomo.ScrollTarget); ok {
+		if child, ok := window.child.element.(tomo.ScrollTarget); ok {
 			sum := scrollSum { }
 			sum.add(buttonEvent.Detail, window, buttonEvent.State)
 			window.compressScrollSum(buttonEvent, &sum)
@@ -215,7 +219,7 @@ func (window *window) handleButtonPress (
 				float64(sum.x), float64(sum.y))
 		}
 	} else {
-		if child, ok := window.child.(tomo.MouseTarget); ok {
+		if child, ok := window.child.element.(tomo.MouseTarget); ok {
 			child.HandleMouseDown (
 				int(buttonEvent.EventX),
 				int(buttonEvent.EventY),
@@ -223,6 +227,7 @@ func (window *window) handleButtonPress (
 		}
 	}
 	
+	window.system.afterEvent()
 }
 
 func (window *window) handleButtonRelease (
@@ -231,7 +236,7 @@ func (window *window) handleButtonRelease (
 ) {
 	if window.child == nil { return }
 	
-	if child, ok := window.child.(tomo.MouseTarget); ok {
+	if child, ok := window.child.element.(tomo.MouseTarget); ok {
 		buttonEvent := *event.ButtonReleaseEvent
 		if buttonEvent.Detail >= 4 && buttonEvent.Detail <= 7 { return }
 		child.HandleMouseUp (
@@ -239,6 +244,8 @@ func (window *window) handleButtonRelease (
 			int(buttonEvent.EventY),
 			input.Button(buttonEvent.Detail))
 	}
+	
+	window.system.afterEvent()
 }
 
 func (window *window) handleMotionNotify (
@@ -247,12 +254,14 @@ func (window *window) handleMotionNotify (
 ) {
 	if window.child == nil { return }
 	
-	if child, ok := window.child.(tomo.MotionTarget); ok {
+	if child, ok := window.child.element.(tomo.MotionTarget); ok {
 		motionEvent := window.compressMotionNotify(*event.MotionNotifyEvent)
 		child.HandleMotion (
 			int(motionEvent.EventX),
 			int(motionEvent.EventY))
 	}
+	
+	window.system.afterEvent()
 }
 
 func (window *window) handleSelectionNotify (
diff --git a/backends/x/system.go b/backends/x/system.go
new file mode 100644
index 0000000..6b53011
--- /dev/null
+++ b/backends/x/system.go
@@ -0,0 +1,109 @@
+package x
+
+import "image"
+import "git.tebibyte.media/sashakoshka/tomo"
+import "git.tebibyte.media/sashakoshka/tomo/canvas"
+
+type entitySet map[*entity] struct { }
+
+func (set entitySet) Empty () bool {
+	return len(set) == 0
+}
+
+func (set entitySet) Has (entity *entity) bool {
+	_, ok := set[entity]
+	return ok
+}
+
+func (set entitySet) Add (entity *entity) {
+	set[entity] = struct { } { }
+}
+
+type system struct {
+	child   *entity
+	focused *entity
+	canvas  canvas.BasicCanvas
+
+	theme  tomo.Theme
+	config tomo.Config
+
+	invalidateIgnore bool
+	drawingInvalid   entitySet
+	anyLayoutInvalid bool
+
+	pushFunc func (image.Rectangle)
+}
+
+func (system *system) initialize () {
+	system.drawingInvalid = make(entitySet)
+}
+
+func (system *system) SetTheme (theme tomo.Theme) {
+	system.theme = theme
+	if system.child == nil { return }
+	if child, ok := system.child.element.(tomo.Themeable); ok {
+		child.SetTheme(theme)
+	}
+}
+
+func (system *system) SetConfig (config tomo.Config) {
+	system.config = config
+	if system.child == nil { return }
+	if child, ok := system.child.element.(tomo.Configurable); ok {
+		child.SetConfig(config)
+	}
+}
+
+func (system *system) resizeChildToFit () {
+	system.child.bounds        = system.canvas.Bounds()
+	system.child.clippedBounds = system.child.bounds
+	system.child.Invalidate()
+	if system.child.isContainer {
+		system.child.InvalidateLayout()
+	}
+}
+
+func (system *system) afterEvent () {
+	if system.anyLayoutInvalid {
+		system.layout(system.child, false)
+		system.anyLayoutInvalid = false
+	}
+	system.draw()
+}
+
+func (system *system) layout (entity *entity, force bool) {
+	if entity == nil { return }
+	if entity.layoutInvalid == true || force {
+		entity.element.(tomo.Container).Layout()
+		entity.layoutInvalid = false
+		force = true
+	}
+
+	for _, child := range entity.children {
+		system.layout(child, force)
+	}
+}
+
+func (system *system) draw () {
+	finalBounds := image.Rectangle { }
+
+	// ignore invalidations that result from drawing elements, because if an
+	// element decides to do that it really needs to rethink its life
+	// choices.
+	system.invalidateIgnore = true
+	defer func () { system.invalidateIgnore = false } ()
+
+	for entity := range system.drawingInvalid {
+		entity.element.Draw (canvas.Cut (
+			system.canvas,
+			entity.clippedBounds))
+		finalBounds = finalBounds.Union(entity.clippedBounds)
+	}
+	system.drawingInvalid = make(entitySet)
+
+	// TODO: don't just union all the bounds together, we can definetly
+	// consolidateupdated regions more efficiently than this.
+	if !finalBounds.Empty() {
+		system.pushFunc(finalBounds)
+	}
+}
diff --git a/backends/x/window.go b/backends/x/window.go
index 0253994..eb661ac 100644
--- a/backends/x/window.go
+++ b/backends/x/window.go
@@ -13,20 +13,16 @@ import "github.com/jezek/xgbutil/mousebind"
 import "github.com/jezek/xgbutil/xgraphics"
 import "git.tebibyte.media/sashakoshka/tomo"
 import "git.tebibyte.media/sashakoshka/tomo/data"
-import "git.tebibyte.media/sashakoshka/tomo/input"
 import "git.tebibyte.media/sashakoshka/tomo/canvas"
-// import "runtime/debug"
 
 type mainWindow struct { *window }
 type menuWindow struct { *window }
 type window struct {
+	system
+	
 	backend *Backend
 	xWindow *xwindow.Window
 	xCanvas *xgraphics.Image
-	canvas  canvas.BasicCanvas
-	child   *entity
-	focused *entity
-	onClose func ()
 
 	title, application string
 
@@ -34,15 +30,14 @@ type window struct {
 	hasModal    bool
 	shy         bool
 
-	theme  tomo.Theme
-	config tomo.Config
-
 	selectionRequest *selectionRequest
 	selectionClaim   *selectionClaim
 
 	metrics struct {
 		bounds image.Rectangle
 	}
+
+	onClose func ()
 }
 
 func (backend *Backend) NewWindow (
@@ -53,6 +48,10 @@ func (backend *Backend) NewWindow (
 ) {
 	if backend == nil { panic("nil backend") }
 	window, err := backend.newWindow(bounds, false)
+
+	window.system.initialize()
+	window.system.pushFunc = window.paste
+	
 	output = mainWindow { window }
 	return output, err
 }
@@ -136,69 +135,24 @@ func (backend *Backend) newWindow (
 	return
 }
 
-func (window *window) NotifyMinimumSizeChange (child tomo.Element) {
-	window.childMinimumSizeChangeCallback(child.MinimumSize())
-}
-
 func (window *window) Window () tomo.Window {
 	return window
 }
 
-func (window *window) RequestFocus (
-	child tomo.Focusable,
-) (
-	granted bool,
-) {
-	return true
-}
-
-func (window *window) RequestFocusNext (child tomo.Focusable) {
-	if child, ok := window.child.(tomo.Focusable); ok {
-		if !child.HandleFocus(input.KeynavDirectionForward) {
-			child.HandleUnfocus()
-		}
-	}
-}
-
-func (window *window) RequestFocusPrevious (child tomo.Focusable) {
-	if child, ok := window.child.(tomo.Focusable); ok {
-		if !child.HandleFocus(input.KeynavDirectionBackward) {
-			child.HandleUnfocus()
-		}
-	}
-}
-
 func (window *window) Adopt (child tomo.Element) {
 	// disown previous child
 	if window.child != nil {
-		window.child.SetParent(nil)
-		window.child.DrawTo(nil, image.Rectangle { }, nil)
+		window.child.unbind()
+		window.child = nil
 	}
 
+	// adopt new child
 	if child != nil {
-		// adopt new child
-		window.child = child
-		child.SetParent(window)
-		if newChild, ok := child.(tomo.Themeable); ok {
-			newChild.SetTheme(window.theme)
-		}
-		if newChild, ok := child.(tomo.Configurable); ok {
-			newChild.SetConfig(window.config)
-		}
-		if child != nil {
-			if !window.childMinimumSizeChangeCallback(child.MinimumSize()) {
-				window.resizeChildToFit()
-				window.redrawChildEntirely()
-			}
-		}
+		window.child = bind(nil, window, child)
+		window.resizeChildToFit()
 	}
 }
 
-func (window *window) Child () (child tomo.Element) {
-	child = window.child
-	return
-}
-
 func (window *window) SetTitle (title string) {
 	window.title = title
 	ewmh.WmNameSet (
@@ -317,43 +271,6 @@ func (window menuWindow) Pin () {
 	// TODO iungrab keyboard and mouse
 }
 
-func (window *window) grabInput () {
-	keybind.GrabKeyboard(window.backend.connection, window.xWindow.Id)
-	mousebind.GrabPointer (
-		window.backend.connection,
-		window.xWindow.Id,
-		window.backend.connection.RootWin(), 0)
-}
-
-func (window *window) ungrabInput () {
-	keybind.UngrabKeyboard(window.backend.connection)
-	mousebind.UngrabPointer(window.backend.connection)
-}
-
-func (window *window) inheritProperties (parent *window) {
-	window.SetApplicationName(parent.application)
-}
-
-func (window *window) setType (ty string) error {
-	return ewmh.WmWindowTypeSet (
-		window.backend.connection,
-		window.xWindow.Id,
-		[]string { "_NET_WM_WINDOW_TYPE_" + ty })
-}
-
-func (window *window) setClientLeader (leader *window) error {
-	hints, _ := icccm.WmHintsGet(window.backend.connection, window.xWindow.Id)
-	if hints == nil {
-		hints = &icccm.Hints { }
-	}
-	hints.Flags |= icccm.HintWindowGroup
-	hints.WindowGroup = leader.xWindow.Id
-	return icccm.WmHintsSet (
-		window.backend.connection,
-		window.xWindow.Id,
-		hints)
-}
-
 func (window *window) Show () {
 	if window.child == nil {
 		window.xCanvas.For (func (x, y int) xgraphics.BGRA {
@@ -362,7 +279,7 @@ func (window *window) Show () {
 
 		window.pushRegion(window.xCanvas.Bounds())
 	}
-	
+
 	window.xWindow.Map()
 	if window.shy { window.grabInput() }
 }
@@ -417,18 +334,41 @@ func (window *window) OnClose (callback func ()) {
 	window.onClose = callback
 }
 
-func (window *window) SetTheme (theme tomo.Theme) {
-	window.theme = theme
-	if child, ok := window.child.(tomo.Themeable); ok {
-		child.SetTheme(theme)
-	}
+func (window *window) grabInput () {
+	keybind.GrabKeyboard(window.backend.connection, window.xWindow.Id)
+	mousebind.GrabPointer (
+		window.backend.connection,
+		window.xWindow.Id,
+		window.backend.connection.RootWin(), 0)
 }
 
-func (window *window) SetConfig (config tomo.Config) {
-	window.config = config
-	if child, ok := window.child.(tomo.Configurable); ok {
-		child.SetConfig(config)
+func (window *window) ungrabInput () {
+	keybind.UngrabKeyboard(window.backend.connection)
+	mousebind.UngrabPointer(window.backend.connection)
+}
+
+func (window *window) inheritProperties (parent *window) {
+	window.SetApplicationName(parent.application)
+}
+
+func (window *window) setType (ty string) error {
+	return ewmh.WmWindowTypeSet (
+		window.backend.connection,
+		window.xWindow.Id,
+		[]string { "_NET_WM_WINDOW_TYPE_" + ty })
+}
+
+func (window *window) setClientLeader (leader *window) error {
+	hints, _ := icccm.WmHintsGet(window.backend.connection, window.xWindow.Id)
+	if hints == nil {
+		hints = &icccm.Hints { }
 	}
+	hints.Flags |= icccm.HintWindowGroup
+	hints.WindowGroup = leader.xWindow.Id
+	return icccm.WmHintsSet (
+		window.backend.connection,
+		window.xWindow.Id,
+		hints)
 }
 
 func (window *window) reallocateCanvas () {
@@ -464,26 +404,6 @@ func (window *window) reallocateCanvas () {
 	
 }
 
-func (window *window) redrawChildEntirely () {
-	window.paste(window.canvas.Bounds())
-	window.pushRegion(window.canvas.Bounds())
-}
-
-func (window *window) resizeChildToFit () {
-	window.skipChildDrawCallback = true
-	window.child.DrawTo (
-		window.canvas,
-		window.canvas.Bounds(),
-		window.childDrawCallback)
-	window.skipChildDrawCallback = false
-}
-
-func (window *window) childDrawCallback (region image.Rectangle) {
-	if window.skipChildDrawCallback { return }
-	window.paste(region)
-	window.pushRegion(region)
-}
-
 func (window *window) paste (region image.Rectangle) {
 	canvas := canvas.Cut(window.canvas, region)
 	data, stride := canvas.Buffer()
@@ -492,7 +412,6 @@ func (window *window) paste (region image.Rectangle) {
 	dstStride := window.xCanvas.Stride
 	dstData   := window.xCanvas.Pix
 	
-	// debug.PrintStack()
 	for y := bounds.Min.Y; y < bounds.Max.Y; y ++ {
 		srcYComponent := y * stride
 		dstYComponent := y * dstStride
@@ -507,6 +426,18 @@ func (window *window) paste (region image.Rectangle) {
 	}
 }
 
+func (window *window) pushRegion (region image.Rectangle) {
+	if window.xCanvas == nil { panic("whoopsie!!!!!!!!!!!!!!") }
+	image, ok := window.xCanvas.SubImage(region).(*xgraphics.Image)
+	if ok {
+		image.XDraw()
+		image.XExpPaint (
+			window.xWindow.Id,
+			image.Bounds().Min.X,
+			image.Bounds().Min.Y)
+	}
+}
+
 func (window *window) childMinimumSizeChangeCallback (width, height int) (resized bool) {
 	icccm.WmNormalHintsSet (
 		window.backend.connection,
@@ -528,15 +459,3 @@ func (window *window) childMinimumSizeChangeCallback (width, height int) (resize
 
 	return false
 }
-
-func (window *window) pushRegion (region image.Rectangle) {
-	if window.xCanvas == nil { panic("whoopsie!!!!!!!!!!!!!!") }
-	image, ok := window.xCanvas.SubImage(region).(*xgraphics.Image)
-	if ok {
-		image.XDraw()
-		image.XExpPaint (
-			window.xWindow.Id,
-			image.Bounds().Min.X,
-			image.Bounds().Min.Y)
-	}
-}
diff --git a/backends/x/x.go b/backends/x/x.go
index 40c3021..ec69708 100644
--- a/backends/x/x.go
+++ b/backends/x/x.go
@@ -67,6 +67,9 @@ func (backend *Backend) Run () (err error) {
 			<- pingAfter
 		case callback := <- backend.doChannel:
 			callback()
+			for _, window := range backend.windows {
+				window.system.afterEvent()
+			}
 		case <- pingQuit:
 			return
 		}
diff --git a/elements/testing/artist.go b/elements/testing/artist.go
index cd2d848..91faa0a 100644
--- a/elements/testing/artist.go
+++ b/elements/testing/artist.go
@@ -26,7 +26,7 @@ func NewArtist () *Artist {
 
 func (element *Artist) Bind (entity tomo.Entity) {
 	element.entity = entity
-	entity.SetMinimumSize(240, 240)
+	if entity != nil { entity.SetMinimumSize(240, 240) }
 }
 
 func (element *Artist) Draw (destination canvas.Canvas) {
diff --git a/window.go b/window.go
index 1813a81..a88b2c8 100644
--- a/window.go
+++ b/window.go
@@ -15,9 +15,6 @@ type Window interface {
 	// these at one time.
 	Adopt (Element)
 
-	// Child returns the root element of the window.
-	Child () Element
-
 	// SetTitle sets the title that appears on the window's title bar. This
 	// method might have no effect with some backends.
 	SetTitle (string)