diff --git a/dom/container.go b/dom/container.go
index fb8c991..a969bdd 100644
--- a/dom/container.go
+++ b/dom/container.go
@@ -18,16 +18,18 @@ package dom
 
 import (
 	"fmt"
-	"github.com/rkosegi/yaml-toolkit/utils"
 	"io"
 	"regexp"
 	"strconv"
 	"strings"
+
+	"github.com/rkosegi/yaml-toolkit/utils"
 )
 
 var (
 	listPathRe = regexp.MustCompile("\\[\\d+]$")
 	nilLeaf    = LeafNode(nil)
+	b          = &containerFactory{}
 )
 
 type containerImpl struct {
@@ -319,7 +321,7 @@ func (f *containerFactory) FromReader(r io.Reader, fn DecoderFunc) (ContainerBui
 }
 
 func Builder() ContainerFactory {
-	return &containerFactory{}
+	return b
 }
 
 var _ ContainerBuilder = &containerBuilderImpl{}
diff --git a/dom/container_test.go b/dom/container_test.go
index b38ab36..c5d1ab7 100644
--- a/dom/container_test.go
+++ b/dom/container_test.go
@@ -18,15 +18,12 @@ package dom
 
 import (
 	"bytes"
-	"github.com/stretchr/testify/assert"
 	"os"
 	"slices"
 	"strings"
 	"testing"
-)
 
-var (
-	b = Builder()
+	"github.com/stretchr/testify/assert"
 )
 
 func TestBuilderFromYamlString(t *testing.T) {