diff --git a/cmd/go.mod b/cmd/go.mod
index 8bd20442..effde7ff 100644
--- a/cmd/go.mod
+++ b/cmd/go.mod
@@ -3,7 +3,7 @@ module gioui.org/cmd
 go 1.13
 
 require (
-	gioui.org v0.0.0-20200531220444-28bf9e200143
+	gioui.org v0.0.0-20200602100720-c19ed0534297
 	github.com/chromedp/cdproto v0.0.0-20191114225735-6626966fbae4
 	github.com/chromedp/chromedp v0.5.2
 	golang.org/x/image v0.0.0-20190802002840-cff245a6509b
diff --git a/cmd/go.sum b/cmd/go.sum
index aac76283..c62f6eff 100644
--- a/cmd/go.sum
+++ b/cmd/go.sum
@@ -1,6 +1,6 @@
 dmitri.shuralyov.com/gpu/mtl v0.0.0-20190408044501-666a987793e9/go.mod h1:H6x//7gZCb22OMCxBHrMx7a5I7Hp++hsVxbQ4BYO7hU=
-gioui.org v0.0.0-20200531220444-28bf9e200143 h1:B3j67PQaeCzLlleL3ZZgkYgGamJEsGBOqqXsoJ7YgJE=
-gioui.org v0.0.0-20200531220444-28bf9e200143/go.mod h1:AHI9rFr6AEEHCb8EPVtb/p5M+NMJRKH58IOp8O3Je04=
+gioui.org v0.0.0-20200602100720-c19ed0534297 h1:Ia8/4NBUEWj6/I7Q2lTOKoyGd2DBnX6av6N+71ZPTtg=
+gioui.org v0.0.0-20200602100720-c19ed0534297/go.mod h1:AHI9rFr6AEEHCb8EPVtb/p5M+NMJRKH58IOp8O3Je04=
 github.com/BurntSushi/xgb v0.0.0-20160522181843-27f122750802 h1:1BDTz0u9nC3//pOCMdNH+CiXJVYJh5UQNCOBG7jbELc=
 github.com/BurntSushi/xgb v0.0.0-20160522181843-27f122750802/go.mod h1:IVnqGOEym/WlBOVXweHU+Q+/VP0lqqI8lqeDx9IjBqo=
 github.com/chromedp/cdproto v0.0.0-20191114225735-6626966fbae4 h1:QD3KxSJ59L2lxG6MXBjNHxiQO2RmxTQ3XcK+wO44WOg=
diff --git a/example/go.mod b/example/go.mod
index eddd5d99..19299252 100644
--- a/example/go.mod
+++ b/example/go.mod
@@ -3,7 +3,7 @@ module gioui.org/example
 go 1.13
 
 require (
-	gioui.org v0.0.0-20200531220444-28bf9e200143
+	gioui.org v0.0.0-20200602100720-c19ed0534297
 	github.com/go-gl/gl v0.0.0-20190320180904-bf2b1f2f34d7
 	github.com/go-gl/glfw/v3.3/glfw v0.0.0-20191125211704-12ad95a8df72
 	github.com/google/go-github/v24 v24.0.1
diff --git a/example/go.sum b/example/go.sum
index 8e8c30f7..a6cea963 100644
--- a/example/go.sum
+++ b/example/go.sum
@@ -1,7 +1,7 @@
 cloud.google.com/go v0.34.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
 dmitri.shuralyov.com/gpu/mtl v0.0.0-20190408044501-666a987793e9/go.mod h1:H6x//7gZCb22OMCxBHrMx7a5I7Hp++hsVxbQ4BYO7hU=
-gioui.org v0.0.0-20200531220444-28bf9e200143 h1:B3j67PQaeCzLlleL3ZZgkYgGamJEsGBOqqXsoJ7YgJE=
-gioui.org v0.0.0-20200531220444-28bf9e200143/go.mod h1:AHI9rFr6AEEHCb8EPVtb/p5M+NMJRKH58IOp8O3Je04=
+gioui.org v0.0.0-20200602100720-c19ed0534297 h1:Ia8/4NBUEWj6/I7Q2lTOKoyGd2DBnX6av6N+71ZPTtg=
+gioui.org v0.0.0-20200602100720-c19ed0534297/go.mod h1:AHI9rFr6AEEHCb8EPVtb/p5M+NMJRKH58IOp8O3Je04=
 github.com/BurntSushi/xgb v0.0.0-20160522181843-27f122750802/go.mod h1:IVnqGOEym/WlBOVXweHU+Q+/VP0lqqI8lqeDx9IjBqo=
 github.com/go-gl/gl v0.0.0-20190320180904-bf2b1f2f34d7 h1:SCYMcCJ89LjRGwEa0tRluNRiMjZHalQZrVrvTbPh+qw=
 github.com/go-gl/gl v0.0.0-20190320180904-bf2b1f2f34d7/go.mod h1:482civXOzJJCPzJ4ZOX/pwvXBWSnzD4OKMdH4ClKGbk=
diff --git a/example/gophers/ui.go b/example/gophers/ui.go
index 7811d858..38a7fff8 100644
--- a/example/gophers/ui.go
+++ b/example/gophers/ui.go
@@ -352,24 +352,21 @@ type clipCircle struct {
 }
 
 func (c *clipCircle) Layout(gtx layout.Context, w layout.Widget) layout.Dimensions {
-	var m op.MacroOp
-	m.Record(gtx.Ops)
+	m := op.Record(gtx.Ops)
 	dims := w(gtx)
-	m.Stop()
+	call := m.Stop()
 	max := dims.Size.X
 	if dy := dims.Size.Y; dy > max {
 		max = dy
 	}
 	szf := float32(max)
 	rr := szf * .5
-	var stack op.StackOp
-	stack.Push(gtx.Ops)
+	defer op.Push(gtx.Ops).Pop()
 	clip.Rect{
 		Rect: f32.Rectangle{Max: f32.Point{X: szf, Y: szf}},
 		NE:   rr, NW: rr, SE: rr, SW: rr,
 	}.Op(gtx.Ops).Add(gtx.Ops)
-	m.Add()
-	stack.Pop()
+	call.Add(gtx.Ops)
 	return dims
 }
 
diff --git a/example/tabs/slider.go b/example/tabs/slider.go
index ba192fda..f21a6c0e 100644
--- a/example/tabs/slider.go
+++ b/example/tabs/slider.go
@@ -18,9 +18,11 @@ type Slider struct {
 
 	push int
 
-	last *op.Ops
 	next *op.Ops
 
+	nextCall op.CallOp
+	lastCall op.CallOp
+
 	t0     time.Time
 	offset float32
 }
@@ -34,7 +36,8 @@ func (s *Slider) PushRight() { s.push = -1 }
 // Layout lays out widget that can be pushed.
 func (s *Slider) Layout(gtx layout.Context, w layout.Widget) layout.Dimensions {
 	if s.push != 0 {
-		s.last, s.next = s.next, new(op.Ops)
+		s.next = nil
+		s.lastCall = s.nextCall
 		s.offset = float32(s.push)
 		s.t0 = gtx.Now()
 		s.push = 0
@@ -73,20 +76,20 @@ func (s *Slider) Layout(gtx layout.Context, w layout.Widget) layout.Dimensions {
 		if s.next == nil {
 			s.next = new(op.Ops)
 		}
-		s.next.Reset()
 		gtx := gtx
 		gtx.Ops = s.next
+		gtx.Ops.Reset()
+		m := op.Record(gtx.Ops)
 		dims = w(gtx)
+		s.nextCall = m.Stop()
 	}
 
 	if s.offset == 0 {
-		op.CallOp{Ops: s.next}.Add(gtx.Ops)
+		s.nextCall.Add(gtx.Ops)
 		return dims
 	}
 
-	var stack op.StackOp
-	stack.Push(gtx.Ops)
-	defer stack.Pop()
+	defer op.Push(gtx.Ops).Pop()
 
 	offset := smooth(s.offset)
 
@@ -94,22 +97,22 @@ func (s *Slider) Layout(gtx layout.Context, w layout.Widget) layout.Dimensions {
 		op.TransformOp{}.Offset(f32.Point{
 			X: float32(dims.Size.X) * (offset - 1),
 		}).Add(gtx.Ops)
-		op.CallOp{Ops: s.last}.Add(gtx.Ops)
+		s.lastCall.Add(gtx.Ops)
 
 		op.TransformOp{}.Offset(f32.Point{
 			X: float32(dims.Size.X),
 		}).Add(gtx.Ops)
-		op.CallOp{Ops: s.next}.Add(gtx.Ops)
+		s.nextCall.Add(gtx.Ops)
 	} else {
 		op.TransformOp{}.Offset(f32.Point{
 			X: float32(dims.Size.X) * (offset + 1),
 		}).Add(gtx.Ops)
-		op.CallOp{Ops: s.last}.Add(gtx.Ops)
+		s.lastCall.Add(gtx.Ops)
 
 		op.TransformOp{}.Offset(f32.Point{
 			X: float32(-dims.Size.X),
 		}).Add(gtx.Ops)
-		op.CallOp{Ops: s.next}.Add(gtx.Ops)
+		s.nextCall.Add(gtx.Ops)
 	}
 	return dims
 }