diff --git a/common/reflect/marshal.go b/common/reflect/marshal.go
index 42f47385..2b224b45 100644
--- a/common/reflect/marshal.go
+++ b/common/reflect/marshal.go
@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"reflect"
+	"slices"
 	"strings"
 
 	cnet "github.com/xtls/xray-core/common/net"
@@ -31,9 +32,6 @@ func JSONMarshalWithoutEscape(t interface{}) ([]byte, error) {
 }
 
 func marshalTypedMessage(v *cserial.TypedMessage, ignoreNullValue bool, insertTypeInfo bool) interface{} {
-	if v == nil {
-		return nil
-	}
 	tmsg, err := v.GetInstance()
 	if err != nil {
 		return nil
@@ -194,29 +192,28 @@ func marshalKnownType(v interface{}, ignoreNullValue bool, insertTypeInfo bool)
 	}
 }
 
+var valueKinds = []reflect.Kind{
+	reflect.Bool,
+	reflect.Int,
+	reflect.Int8,
+	reflect.Int16,
+	reflect.Int32,
+	reflect.Int64,
+	reflect.Uint,
+	reflect.Uint8,
+	reflect.Uint16,
+	reflect.Uint32,
+	reflect.Uint64,
+	reflect.Uintptr,
+	reflect.Float32,
+	reflect.Float64,
+	reflect.Complex64,
+	reflect.Complex128,
+	reflect.String,
+}
+
 func isValueKind(kind reflect.Kind) bool {
-	switch kind {
-	case reflect.Bool,
-		reflect.Int,
-		reflect.Int8,
-		reflect.Int16,
-		reflect.Int32,
-		reflect.Int64,
-		reflect.Uint,
-		reflect.Uint8,
-		reflect.Uint16,
-		reflect.Uint32,
-		reflect.Uint64,
-		reflect.Uintptr,
-		reflect.Float32,
-		reflect.Float64,
-		reflect.Complex64,
-		reflect.Complex128,
-		reflect.String:
-		return true
-	default:
-		return false
-	}
+	return slices.Contains(valueKinds, kind)
 }
 
 func marshalInterface(v interface{}, ignoreNullValue bool, insertTypeInfo bool) interface{} {
diff --git a/core/config.go b/core/config.go
index 4390766d..ec9e5aa4 100644
--- a/core/config.go
+++ b/core/config.go
@@ -2,6 +2,7 @@ package core
 
 import (
 	"io"
+	"slices"
 	"strings"
 
 	"github.com/xtls/xray-core/common"
@@ -64,14 +65,11 @@ func GetMergedConfig(args cmdarg.Arg) (string, error) {
 	supported := []string{"json", "yaml", "toml"}
 	for _, file := range args {
 		format := getFormat(file)
-		for _, s := range supported {
-			if s == format {
-				files = append(files, &ConfigSource{
-					Name:   file,
-					Format: format,
-				})
-				break
-			}
+		if slices.Contains(supported, format) {
+			files = append(files, &ConfigSource{
+				Name:   file,
+				Format: format,
+			})
 		}
 	}
 	return ConfigMergedFormFiles(files)