diff --git a/go/asm/menu.go b/go/asm/menu.go
index 13a2c2d..cf34dc4 100644
--- a/go/asm/menu.go
+++ b/go/asm/menu.go
@@ -71,9 +71,9 @@ func (mp *MenuProcessor) ToLines() []byte {
 		case MENU_UP:
 			postLines = vm.NewLine(postLines, vm.INCMP, []string{v.choice, "_"}, nil, nil)
 		case MENU_NEXT:
-			_ = postLines
+			postLines = vm.NewLine(postLines, vm.INCMP, []string{v.choice, ">"}, nil, nil)
 		case MENU_PREVIOUS:
-			_ = postLines
+			postLines = vm.NewLine(postLines, vm.INCMP, []string{v.choice, "<"}, nil, nil)
 		default:
 			postLines = vm.NewLine(postLines, vm.INCMP, []string{v.choice, v.target}, nil, nil)
 		}
@@ -82,5 +82,3 @@ func (mp *MenuProcessor) ToLines() []byte {
 	preLines = vm.NewLine(preLines, vm.HALT, nil, nil, nil)
 	return append(preLines, postLines...)
 }
-
-
diff --git a/go/asm/menu_test.go b/go/asm/menu_test.go
index 8f0d7e7..46e070a 100644
--- a/go/asm/menu_test.go
+++ b/go/asm/menu_test.go
@@ -40,6 +40,8 @@ MOUT 2 "blinky clyde"
 MOUT 99 "tinky-winky"
 HALT
 INCMP 0 foo
+INCMP 1 >
+INCMP 2 <
 INCMP 99 _
 `
 	if r != expect {
diff --git a/go/engine/engine.go b/go/engine/engine.go
index 7c55520..5e0aa98 100644
--- a/go/engine/engine.go
+++ b/go/engine/engine.go
@@ -5,18 +5,12 @@ import (
 	"fmt"
 	"io"
 	"log"
-	"regexp"
 
 	"git.defalsify.org/festive/resource"
 	"git.defalsify.org/festive/state"
 	"git.defalsify.org/festive/vm"
 )
 
-var (
-	inputRegexStr = "^[a-zA-Z0-9].*$"
-	inputRegex = regexp.MustCompile(inputRegexStr)
-)
-
 //type Config struct {
 //	FlagCount uint32
 //	CacheSize uint32
@@ -51,14 +45,6 @@ func(en *Engine) Init(sym string, ctx context.Context) error {
 	return nil
 }
 
-// return descriptive error if client input is invalid
-func checkInput(input []byte) error {
-	if !inputRegex.Match(input) {
-		return fmt.Errorf("Input '%s' does not match format /%s/", input, inputRegexStr)
-	}
-	return nil
-}
-
 // Exec processes user input against the current state of the virtual machine environment.
 //
 // If successfully executed, output of the last execution is available using the WriteResult call.
@@ -70,7 +56,7 @@ func checkInput(input []byte) error {
 // - no current bytecode is available
 // - input processing against bytcode failed
 func (en *Engine) Exec(input []byte, ctx context.Context) (bool, error) {
-	err := checkInput(input)
+	err := vm.CheckInput(input)
 	if err != nil {
 		return true, err
 	}
diff --git a/go/resource/size_test.go b/go/resource/size_test.go
index fd1eca0..d39bb39 100644
--- a/go/resource/size_test.go
+++ b/go/resource/size_test.go
@@ -61,6 +61,7 @@ func TestSizeLimit(t *testing.T) {
 	rs := TestSizeResource{
 		mrs,	
 	}
+	st.Down("test")
 	st.Add("foo", "inky", 4)
 	st.Add("bar", "pinky", 10)
 	st.Add("baz", "blinky", 0)
@@ -107,6 +108,7 @@ func TestSizePages(t *testing.T) {
 	rs := TestSizeResource{
 		mrs,	
 	}
+	st.Down("test")
 	st.Add("foo", "inky", 4)
 	st.Add("bar", "pinky", 10)
 	st.Add("baz", "blinky", 20)
diff --git a/go/state/state.go b/go/state/state.go
index d593ea9..6d7f525 100644
--- a/go/state/state.go
+++ b/go/state/state.go
@@ -72,7 +72,7 @@ func NewState(bitSize uint32) State {
 	} else {
 		st.Flags = []byte{}
 	}
-	st.Down("")
+	//st.Down("")
 	return st
 }
 
@@ -223,7 +223,6 @@ func(st *State) Down(input string) {
 	st.resetCurrent()
 }
 
-
 // Up removes the latest symbol to the command stack, and make the previous symbol current.
 //
 // Frees all symbols and associated values loaded at the previous stack level. Cache capacity is increased by the corresponding amount.
@@ -231,10 +230,10 @@ func(st *State) Down(input string) {
 // Clears mapping and sink.
 //
 // Fails if called at top frame.
-func(st *State) Up() error {
+func(st *State) Up() (string, error) {
 	l := len(st.Cache)
 	if l == 0 {
-		return fmt.Errorf("exit called beyond top frame")
+		return "", fmt.Errorf("exit called beyond top frame")
 	}
 	l -= 1
 	m := st.Cache[l]
@@ -245,8 +244,12 @@ func(st *State) Up() error {
 	}
 	st.Cache = st.Cache[:l]
 	st.execPath = st.execPath[:l]
+	sym := ""
+	if len(st.execPath) > 0 {
+		sym = st.execPath[len(st.execPath)-1]
+	}
 	st.resetCurrent()
-	return nil
+	return sym, nil
 }
 
 // Add adds a cache value under a cache symbol key.
diff --git a/go/state/state_test.go b/go/state/state_test.go
index 7ed746d..254195f 100644
--- a/go/state/state_test.go
+++ b/go/state/state_test.go
@@ -168,6 +168,7 @@ func TestStateCacheUse(t *testing.T) {
 func TestStateDownUp(t *testing.T) {
 	st := NewState(17)
 	st.Down("one")
+	st.Down("two")
 	err := st.Add("foo", "bar", 0)
 	if err != nil {
 		t.Error(err)
@@ -179,15 +180,21 @@ func TestStateDownUp(t *testing.T) {
 	if st.CacheUseSize != 8 {
 		t.Errorf("expected cache use size 8 got %v", st.CacheUseSize)
 	}
-	err = st.Up()
+	s, err := st.Up()
 	if err != nil {
 		t.Error(err)
 	}
-	err = st.Up()
+	if s != "one" {
+		t.Errorf("expected sym 'one', got '%s'", s)
+	}
+	s, err = st.Up()
 	if err != nil {
 		t.Error(err)
 	}
-	err = st.Up()
+	if s != "" {
+		t.Errorf("expected sym '', got '%s'", s)
+	}
+	s, err = st.Up()
 	if err == nil {
 		t.Errorf("expected out of top frame error")
 	}
diff --git a/go/vm/debug.go b/go/vm/debug.go
index 6b912a8..2e885bd 100644
--- a/go/vm/debug.go
+++ b/go/vm/debug.go
@@ -129,22 +129,6 @@ func ParseAll(b []byte, w io.Writer) (int, error) {
 					rs = fmt.Sprintf("%s %s \"%s\"\n", s, r, v)
 				}
 			}
-		case MNEXT:
-			r, v, bb, err := ParseMNext(b)
-			b = bb
-			if err == nil {
-				if w != nil {
-					rs = fmt.Sprintf("%s %s \"%s\"\n", s, r, v)
-				}
-			}
-		case MPREV:
-			r, v, bb, err := ParseMPrev(b)
-			b = bb
-			if err == nil {
-				if w != nil {
-					rs = fmt.Sprintf("%s %s \"%s\"\n", s, r, v)
-				}
-			}
 		}
 		if err != nil {
 			return rn, err
diff --git a/go/vm/debug_test.go b/go/vm/debug_test.go
index 7afd303..3605b10 100644
--- a/go/vm/debug_test.go
+++ b/go/vm/debug_test.go
@@ -91,26 +91,6 @@ func TestToString(t *testing.T) {
 		t.Fatalf("expected:\n\t%v\ngot:\n\t%v", expect, r)
 	}
 
-	b = NewLine(nil, MNEXT, []string{"11", "nextmenu"}, nil, nil) 
-	r, err = ToString(b)
-	if err != nil {
-		t.Fatal(err)
-	}
-	expect = "MNEXT 11 \"nextmenu\"\n"
-	if r != expect {
-		t.Fatalf("expected:\n\t%v\ngot:\n\t%v", expect, r)
-	}
-
-	b = NewLine(nil, MPREV, []string{"222", "previous menu item"}, nil, nil) 
-	r, err = ToString(b)
-	if err != nil {
-		t.Fatal(err)
-	}
-	expect = "MPREV 222 \"previous menu item\"\n"
-	if r != expect {
-		t.Fatalf("expected:\n\t%v\ngot:\n\t%v", expect, r)
-	}
-
 	b = NewLine(nil, MOUT, []string{"1", "foo"}, nil, nil) 
 	r, err = ToString(b)
 	if err != nil {
diff --git a/go/vm/input.go b/go/vm/input.go
new file mode 100644
index 0000000..78b4369
--- /dev/null
+++ b/go/vm/input.go
@@ -0,0 +1,52 @@
+package vm
+
+import (
+	"context"
+	"fmt"
+	"regexp"
+
+	"git.defalsify.org/festive/state"
+)
+
+var (
+	inputRegexStr = "^[a-zA-Z0-9].*$"
+	inputRegex = regexp.MustCompile(inputRegexStr)
+	ctrlInputRegexStr = "^[<>_]$"
+	ctrlInputRegex = regexp.MustCompile(inputRegexStr)
+)
+
+
+func CheckInput(input []byte) error {
+	if !inputRegex.Match(input) {
+		return fmt.Errorf("Input '%s' does not match format /%s/", input, inputRegexStr)
+	}
+	return nil
+}
+
+func applyControlInput(input []byte, st *state.State, ctx context.Context) (string, error) {
+	var err error
+	sym, idx := st.Where()
+	switch input[0] {
+	case '_':
+		sym, err = st.Up()
+		if err != nil {
+			return sym, err
+		}
+	}
+	_ = idx
+	return sym, nil
+}
+
+func ApplyInput(inputString string, st *state.State, ctx context.Context) (string, error) {
+	input := []byte(inputString)
+	if ctrlInputRegex.Match(input) {
+		return applyControlInput(input, st, ctx)
+	}
+
+	err := CheckInput(input)
+	if err != nil {
+		return "", err
+	}
+	st.Down(inputString)
+	return inputString, nil
+}
diff --git a/go/vm/opcodes.go b/go/vm/opcodes.go
index 77855b8..9072b1a 100644
--- a/go/vm/opcodes.go
+++ b/go/vm/opcodes.go
@@ -17,9 +17,7 @@ const (
 	INCMP = 8
 	MSIZE = 9
 	MOUT = 10
-	MNEXT = 11
-	MPREV = 12
-	_MAX = 12
+	_MAX = 10
 )
 
 var (
@@ -35,8 +33,6 @@ var (
 		INCMP: "INCMP",
 		MSIZE: "MSIZE",
 		MOUT: "MOUT",
-		MNEXT: "MNEXT",
-		MPREV: "MPREV",
 	}
 
 	OpcodeIndex = map[string]Opcode {
@@ -51,8 +47,6 @@ var (
 		"INCMP": INCMP,
 		"MSIZE": MSIZE,
 		"MOUT": MOUT,
-		"MNEXT": MNEXT,
-		"MPREV": MPREV,
 	}
 
 )
diff --git a/go/vm/runner.go b/go/vm/runner.go
index 4ae2468..c8b7ae8 100644
--- a/go/vm/runner.go
+++ b/go/vm/runner.go
@@ -44,10 +44,6 @@ func Run(b []byte, st *state.State, rs resource.Resource, ctx context.Context) (
 			b, err = RunMSize(b, st, rs, ctx)
 		case MOUT:
 			b, err = RunMOut(b, st, rs, ctx)
-		case MNEXT:
-			b, err = RunMNext(b, st, rs, ctx)
-		case MPREV:
-			b, err = RunMPrev(b, st, rs, ctx)
 		case HALT:
 			b, err = RunHalt(b, st, rs, ctx)
 			return b, err
@@ -245,26 +241,6 @@ func RunMSize(b []byte, st *state.State, rs resource.Resource, ctx context.Conte
 	return b, err
 }
 
-// RunMNext executes the MNEXT opcode
-func RunMNext(b []byte, st *state.State, rs resource.Resource, ctx context.Context) ([]byte, error) {
-	selector, display, b, err := ParseMNext(b)
-	if err != nil {
-		return b, err
-	}
-	err = rs.SetMenuBrowse(selector, display, false)
-	return b, err
-}
-
-// RunMPrev executes the MPREV opcode
-func RunMPrev(b []byte, st *state.State, rs resource.Resource, ctx context.Context) ([]byte, error) {
-	selector, display, b, err := ParseMPrev(b)
-	if err != nil {
-		return b, err
-	}
-	err = rs.SetMenuBrowse(selector, display, false)
-	return b, err
-}
-
 // RunMOut executes the MOUT opcode
 func RunMOut(b []byte, st *state.State, rs resource.Resource, ctx context.Context) ([]byte, error) {
 	choice, title, b, err := ParseMOut(b)
diff --git a/go/vm/runner_test.go b/go/vm/runner_test.go
index 5be3bd7..ecbbf01 100644
--- a/go/vm/runner_test.go
+++ b/go/vm/runner_test.go
@@ -160,7 +160,8 @@ func TestRunLoadRender(t *testing.T) {
 func TestRunMultiple(t *testing.T) {
 	st := state.NewState(5)
 	rs := TestResource{}
-	b := NewLine(nil, LOAD, []string{"one"}, []byte{0x00}, nil)
+	b := NewLine(nil, MOVE, []string{"test"}, nil, nil)
+	b = NewLine(b, LOAD, []string{"one"}, []byte{0x00}, nil)
 	b = NewLine(b, LOAD, []string{"two"}, []byte{42}, nil)
 	b = NewLine(b, HALT, nil, nil, nil)
 	b, err := Run(b, &st, &rs, context.TODO())
@@ -211,7 +212,8 @@ func TestRunReload(t *testing.T) {
 func TestHalt(t *testing.T) {
 	st := state.NewState(5)
 	rs := TestResource{}
-	b := NewLine([]byte{}, LOAD, []string{"one"}, nil, []uint8{0})
+	b := NewLine(nil, MOVE, []string{"root"}, nil, nil)
+	b = NewLine(b, LOAD, []string{"one"}, nil, []uint8{0})
 	b = NewLine(b, HALT, nil, nil, nil)
 	b = NewLine(b, MOVE, []string{"foo"}, nil, nil)
 	var err error
@@ -336,8 +338,6 @@ func TestRunMenuBrowse(t *testing.T) {
 	var err error
 
 	b := NewLine(nil, MOVE, []string{"foo"}, nil, nil)
-	b = NewLine(b, MNEXT, []string{"11", "two"}, nil, nil)
-	b = NewLine(b, MPREV, []string{"22", "two"}, nil, nil)
 	b = NewLine(b, MOUT, []string{"0", "one"}, nil, nil)
 	b = NewLine(b, MOUT, []string{"1", "two"}, nil, nil)
 	b = NewLine(b, HALT, nil, nil, nil)