diff --git a/gorush/config.go b/gorush/config.go
index 1a85c62..d011673 100644
--- a/gorush/config.go
+++ b/gorush/config.go
@@ -1,4 +1,4 @@
-package main
+package gopush
 
 import (
 	"gopkg.in/yaml.v2"
@@ -52,8 +52,8 @@ func BuildDefaultPushConf() ConfYaml {
 
 	// iOS
 	conf.Ios.Enabled = true
-	conf.Ios.PemCertPath = ""
-	conf.Ios.PemKeyPath = ""
+	conf.Ios.PemCertPath = "cert.pem"
+	conf.Ios.PemKeyPath = "key.pem"
 	conf.Ios.Production = false
 
 	return conf
diff --git a/gorush/const.go b/gorush/const.go
index 237f852..55e4ecd 100644
--- a/gorush/const.go
+++ b/gorush/const.go
@@ -1,4 +1,4 @@
-package main
+package gopush
 
 const (
 	Version = "0.0.1"
diff --git a/gorush/global.go b/gorush/global.go
index 9be2bbd..35974a6 100644
--- a/gorush/global.go
+++ b/gorush/global.go
@@ -1,4 +1,4 @@
-package main
+package gopush
 
 import (
 	"crypto/tls"
diff --git a/gorush/notification.go b/gorush/notification.go
index 69b8dc1..2671ae0 100644
--- a/gorush/notification.go
+++ b/gorush/notification.go
@@ -1,4 +1,4 @@
-package main
+package gopush
 
 import (
 	"github.com/google/go-gcm"
diff --git a/gorush/server.go b/gorush/server.go
index 1d6dc14..0231bd3 100644
--- a/gorush/server.go
+++ b/gorush/server.go
@@ -1,11 +1,9 @@
-package main
+package gopush
 
 import (
 	api "github.com/appleboy/gin-status-api"
 	"github.com/fvbock/endless"
 	"github.com/gin-gonic/gin"
-	apns "github.com/sideshow/apns2"
-	"github.com/sideshow/apns2/certificate"
 	"log"
 	"net/http"
 )
@@ -56,36 +54,6 @@ func GetMainEngine() *gin.Engine {
 	return r
 }
 
-func main() {
-	var err error
-
-	// set default parameters.
-	PushConf = BuildDefaultPushConf()
-
-	// load user define config.
-	PushConf, err = LoadConfYaml("config.yaml")
-
-	if err != nil {
-		log.Printf("Unable to load config file: '%v'", err)
-
-		return
-	}
-
-	if PushConf.Ios.Enabled {
-		CertificatePemIos, err = certificate.FromPemFile(PushConf.Ios.PemKeyPath, "")
-
-		if err != nil {
-			log.Println("Cert Error:", err)
-
-			return
-		}
-
-		if PushConf.Ios.Production {
-			ApnsClient = apns.NewClient(CertificatePemIos).Production()
-		} else {
-			ApnsClient = apns.NewClient(CertificatePemIos).Development()
-		}
-	}
-
+func RunHTTPServer() {
 	endless.ListenAndServe(":"+PushConf.Core.Port, GetMainEngine())
 }
diff --git a/gorush/version.go b/gorush/version.go
index d45b710..ba6a240 100644
--- a/gorush/version.go
+++ b/gorush/version.go
@@ -1,4 +1,4 @@
-package main
+package gopush
 
 import (
 	"fmt"
@@ -7,7 +7,7 @@ import (
 )
 
 func PrintGoPushVersion() {
-	fmt.Printf(`GoPush %s Compiler: %s %s Copyright (C) 2016 Bo-Yi Wu, Inc.`,
+	fmt.Printf(`GoPush %s, Compiler: %s %s, Copyright (C) 2016 Bo-Yi Wu, Inc.`,
 		Version,
 		runtime.Compiler,
 		runtime.Version())
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..bc702aa
--- /dev/null
+++ b/main.go
@@ -0,0 +1,61 @@
+package main
+
+import (
+	"flag"
+	"github.com/appleboy/gopush/gopush"
+	"github.com/sideshow/apns2/certificate"
+	apns "github.com/sideshow/apns2"
+	"log"
+)
+
+func main() {
+	version := flag.Bool("v", false, "gopush version")
+	confPath := flag.String("c", "", "yaml configuration file path for gopush")
+	port := flag.String("p", "", "port number for gopush")
+
+	flag.Parse()
+
+	if *version {
+		gopush.PrintGoPushVersion()
+		return
+	}
+
+	var err error
+
+	// set default parameters.
+	gopush.PushConf = gopush.BuildDefaultPushConf()
+
+	// load user define config.
+	if *confPath != "" {
+		gopush.PushConf, err = gopush.LoadConfYaml(*confPath)
+
+		if err != nil {
+			log.Printf("Unable to load yaml config file: '%v'", err)
+
+			return
+		}
+	}
+
+	if gopush.PushConf.Ios.Enabled {
+		gopush.CertificatePemIos, err = certificate.FromPemFile(gopush.PushConf.Ios.PemKeyPath, "")
+
+		if err != nil {
+			log.Println("Cert Error:", err)
+
+			return
+		}
+
+		if gopush.PushConf.Ios.Production {
+			gopush.ApnsClient = apns.NewClient(gopush.CertificatePemIos).Production()
+		} else {
+			gopush.ApnsClient = apns.NewClient(gopush.CertificatePemIos).Development()
+		}
+	}
+
+	// overwrite server port
+	if *port != "" {
+		gopush.PushConf.Core.Port = *port
+	}
+
+	gopush.RunHTTPServer()
+}