diff --git a/internal/jsre/jsre.go b/internal/jsre/jsre.go
index 72a39be36c..7a8b44278a 100644
--- a/internal/jsre/jsre.go
+++ b/internal/jsre/jsre.go
@@ -106,9 +106,9 @@ func randomSource() *rand.Rand {
 func (re *JSRE) runEventLoop() {
 	defer close(re.closed)
 
-	vm := goja.New()
+	re.vm = goja.New()
 	r := randomSource()
-	vm.SetRandSource(r.Float64)
+	re.vm.SetRandSource(r.Float64)
 
 	registry := map[*jsTimer]*jsTimer{}
 	ready := make(chan *jsTimer)
@@ -150,22 +150,22 @@ func (re *JSRE) runEventLoop() {
 		}
 		return goja.Undefined()
 	}
-	vm.Set("_setTimeout", setTimeout)
-	vm.Set("_setInterval", setInterval)
-	vm.RunString(`var setTimeout = function(args) {
+	re.vm.Set("_setTimeout", setTimeout)
+	re.vm.Set("_setInterval", setInterval)
+	re.vm.RunString(`var setTimeout = function(args) {
 		if (arguments.length < 1) {
 			throw TypeError("Failed to execute 'setTimeout': 1 argument required, but only 0 present.");
 		}
 		return _setTimeout.apply(this, arguments);
 	}`)
-	vm.RunString(`var setInterval = function(args) {
+	re.vm.RunString(`var setInterval = function(args) {
 		if (arguments.length < 1) {
 			throw TypeError("Failed to execute 'setInterval': 1 argument required, but only 0 present.");
 		}
 		return _setInterval.apply(this, arguments);
 	}`)
-	vm.Set("clearTimeout", clearTimeout)
-	vm.Set("clearInterval", clearTimeout)
+	re.vm.Set("clearTimeout", clearTimeout)
+	re.vm.Set("clearInterval", clearTimeout)
 
 	var waitForCallbacks bool
 
@@ -185,9 +185,9 @@ loop:
 				arguments = make([]interface{}, 1)
 			}
 			arguments[0] = timer.call.Arguments[0]
-			call, isFunc := goja.AssertFunction(vm.Get(`Function.call.call`))
+			call, isFunc := goja.AssertFunction(timer.call.Arguments[0])
 			if !isFunc {
-				panic(vm.ToValue("js error: Function.call.call is not a function"))
+				panic(re.vm.ToValue("js error: timer/timeout callback is not a function"))
 			}
 			call(goja.Null(), timer.call.Arguments...)
 
@@ -202,7 +202,7 @@ loop:
 			}
 		case req := <-re.evalQueue:
 			// run the code, send the result back
-			req.fn(vm)
+			req.fn(re.vm)
 			close(req.done)
 			if waitForCallbacks && (len(registry) == 0) {
 				break loop
diff --git a/internal/jsre/jsre_test.go b/internal/jsre/jsre_test.go
index bcb6e0dd23..65bda1ff7d 100644
--- a/internal/jsre/jsre_test.go
+++ b/internal/jsre/jsre_test.go
@@ -20,25 +20,24 @@ import (
 	"io/ioutil"
 	"os"
 	"path"
+	"reflect"
 	"testing"
 	"time"
 
-	"github.com/robertkrimen/otto"
+	"github.com/dop251/goja"
 )
 
-type testNativeObjectBinding struct{}
+type testNativeObjectBinding struct {
+	vm *goja.Runtime
+}
 
 type msg struct {
 	Msg string
 }
 
-func (no *testNativeObjectBinding) TestMethod(call otto.FunctionCall) otto.Value {
-	m, err := call.Argument(0).ToString()
-	if err != nil {
-		return otto.UndefinedValue()
-	}
-	v, _ := call.Otto.ToValue(&msg{m})
-	return v
+func (no *testNativeObjectBinding) TestMethod(call goja.FunctionCall) goja.Value {
+	m := call.Argument(0).ToString().String()
+	return no.vm.ToValue(&msg{m})
 }
 
 func newWithTestJS(t *testing.T, testjs string) (*JSRE, string) {
@@ -51,7 +50,8 @@ func newWithTestJS(t *testing.T, testjs string) (*JSRE, string) {
 			t.Fatal("cannot create test.js:", err)
 		}
 	}
-	return New(dir, os.Stdout), dir
+	jsre := New(dir, os.Stdout)
+	return jsre, dir
 }
 
 func TestExec(t *testing.T) {
@@ -66,11 +66,11 @@ func TestExec(t *testing.T) {
 	if err != nil {
 		t.Errorf("expected no error, got %v", err)
 	}
-	if !val.IsString() {
+	if val.ExportType().Kind() != reflect.String {
 		t.Errorf("expected string value, got %v", val)
 	}
 	exp := "testMsg"
-	got, _ := val.ToString()
+	got := val.ToString().String()
 	if exp != got {
 		t.Errorf("expected '%v', got '%v'", exp, got)
 	}
@@ -90,11 +90,11 @@ func TestNatto(t *testing.T) {
 	if err != nil {
 		t.Errorf("expected no error, got %v", err)
 	}
-	if !val.IsString() {
+	if val.ExportType().Kind() != reflect.String {
 		t.Errorf("expected string value, got %v", val)
 	}
 	exp := "testMsg"
-	got, _ := val.ToString()
+	got := val.ToString().String()
 	if exp != got {
 		t.Errorf("expected '%v', got '%v'", exp, got)
 	}
@@ -105,7 +105,7 @@ func TestBind(t *testing.T) {
 	jsre := New("", os.Stdout)
 	defer jsre.Stop(false)
 
-	jsre.Bind("no", &testNativeObjectBinding{})
+	jsre.Bind("no", &testNativeObjectBinding{vm: jsre.vm})
 
 	_, err := jsre.Run(`no.TestMethod("testMsg")`)
 	if err != nil {
@@ -125,11 +125,11 @@ func TestLoadScript(t *testing.T) {
 	if err != nil {
 		t.Errorf("expected no error, got %v", err)
 	}
-	if !val.IsString() {
+	if val.ExportType().Kind() != reflect.String {
 		t.Errorf("expected string value, got %v", val)
 	}
 	exp := "testMsg"
-	got, _ := val.ToString()
+	got := val.ToString().String()
 	if exp != got {
 		t.Errorf("expected '%v', got '%v'", exp, got)
 	}
diff --git a/vendor/github.com/dop251/goja/func.go b/vendor/github.com/dop251/goja/func.go
index a4927b0097..5755c61169 100644
--- a/vendor/github.com/dop251/goja/func.go
+++ b/vendor/github.com/dop251/goja/func.go
@@ -1,6 +1,8 @@
 package goja
 
-import "reflect"
+import (
+	"reflect"
+)
 
 type baseFuncObject struct {
 	baseObject
diff --git a/vendor/github.com/dop251/goja/value.go b/vendor/github.com/dop251/goja/value.go
index 39225dbd0d..8bf103afc9 100644
--- a/vendor/github.com/dop251/goja/value.go
+++ b/vendor/github.com/dop251/goja/value.go
@@ -436,7 +436,7 @@ func (p *valueProperty) get(this Value) Value {
 		}
 		return _undefined
 	}
-	call, _ := p.getterFunc.self.assertCallable()
+	call, r := p.getterFunc.self.assertCallable()
 	return call(FunctionCall{
 		This: this,
 	})