diff --git a/cmd/cmd_config.go b/cmd/cmd_config.go
index 8a79062..be68b21 100644
--- a/cmd/cmd_config.go
+++ b/cmd/cmd_config.go
@@ -16,9 +16,13 @@ import (
 var commandBuild = &cobra.Command{
 	Use:   "build",
 	Short: "Build configuration",
-	Args:  cobra.ExactArgs(2),
+	Args:  cobra.MinimumNArgs(1),
 	Run: func(cmd *cobra.Command, args []string) {
-		err := build(args[0], args[1])
+		var optionsPath string
+		if len(args) > 1 {
+			optionsPath = args[1]
+		}
+		err := build(args[0], optionsPath)
 		if err != nil {
 			log.Fatal(err)
 		}
@@ -32,15 +36,20 @@ func init() {
 func build(path string, optionsPath string) error {
 	if workingDir != "" {
 		path = filepath.Join(workingDir, path)
-		optionsPath = filepath.Join(workingDir, optionsPath)
+		if optionsPath != "" {
+			optionsPath = filepath.Join(workingDir, optionsPath)
+		}
 	}
 	options, err := readConfigAt(path)
 	if err != nil {
 		return err
 	}
-	configOptions, err := readConfigOptionsAt(optionsPath)
-	if err != nil {
-		return err
+	configOptions := shared.DefaultConfigOptions()
+	if optionsPath != "" {
+		configOptions, err = readConfigOptionsAt(optionsPath)
+		if err != nil {
+			return err
+		}
 	}
 	config, err := shared.BuildConfigJson(*configOptions, *options)
 	if err != nil {
diff --git a/shared/config.go b/shared/config.go
index 0a85573..b876b21 100644
--- a/shared/config.go
+++ b/shared/config.go
@@ -8,6 +8,7 @@ import (
 	"net/netip"
 	"net/url"
 	"strings"
+	"time"
 
 	C "github.com/sagernet/sing-box/constant"
 	"github.com/sagernet/sing-box/option"
@@ -54,6 +55,46 @@ type TLSTricks struct {
 	PaddingSize        string `json:"tls-padding-size"`
 }
 
+func DefaultConfigOptions() *ConfigOptions {
+	return &ConfigOptions{
+		ExecuteAsIs:             false,
+		LogLevel:                "info",
+		ResolveDestination:      false,
+		IPv6Mode:                option.DomainStrategy(dns.DomainStrategyAsIS),
+		RemoteDnsAddress:        "1.1.1.1",
+		RemoteDnsDomainStrategy: option.DomainStrategy(dns.DomainStrategyAsIS),
+		DirectDnsAddress:        "1.1.1.1",
+		DirectDnsDomainStrategy: option.DomainStrategy(dns.DomainStrategyAsIS),
+		MixedPort:               2334,
+		LocalDnsPort:            6450,
+		MTU:                     9000,
+		StrictRoute:             true,
+		TUNStack:                "mixed",
+		ConnectionTestUrl:       "https://cp.cloudflare.com/",
+		URLTestInterval:         option.Duration(10 * time.Minute),
+		EnableClashApi:          true,
+		ClashApiPort:            6756,
+		EnableTun:               true,
+		SetSystemProxy:          true,
+		BypassLAN:               false,
+		AllowConnectionFromLAN:  false,
+		EnableFakeDNS:           false,
+		EnableDNSRouting:        false,
+		IndependentDNSCache:     false,
+		GeoIPPath:               "geoip.db",
+		GeoSitePath:             "geosite.db",
+		Rules:                   []Rule{},
+		TLSTricks: TLSTricks{
+			EnableFragment:     false,
+			FragmentSize:       "10-100",
+			FragmentSleep:      "50-200",
+			EnableMixedSNICase: false,
+			EnablePadding:      false,
+			PaddingSize:        "100-200",
+		},
+	}
+}
+
 func BuildConfigJson(configOpt ConfigOptions, input option.Options) (string, error) {
 	options := BuildConfig(configOpt, input)
 	var buffer bytes.Buffer