diff --git a/build-all.sh b/build-all.sh
index e323188..35abca3 100755
--- a/build-all.sh
+++ b/build-all.sh
@@ -31,11 +31,19 @@ wget https://github.com/v2ray/geoip/raw/release/geoip.dat -O geoip.dat
 SCRIPT_NAME=`basename "$0"`
 FAILURES=""
 
+PACKAGE_NAME="github.com/p4gefau1t/trojan-go"
+VERSION=`git describe`
+COMMIT=`git rev-parse HEAD`
+
+VAR_SETTING=""
+VAR_SETTING="$VAR_SETTING -X $PACKAGE_NAME/constant.Version=$VERSION"
+VAR_SETTING="$VAR_SETTING -X $PACKAGE_NAME/constant.Commit=$COMMIT"
+
 for PLATFORM in $PLATFORMS; do
   GOOS=${PLATFORM%/*}
   GOARCH=${PLATFORM#*/}
   ZIP_FILENAME="trojan-go-${GOOS}-${GOARCH}.zip"
-  CMD="CGO_ENABLE=0 GOOS=${GOOS} GOARCH=${GOARCH} go build -tags \"full\" -o temp -ldflags=\"-s -w\""
+  CMD="CGO_ENABLE=0 GOOS=${GOOS} GOARCH=${GOARCH} go build -tags \"full\" -o temp -ldflags=\"-s -w ${VAR_SETTING}\""
   echo "${CMD}"
   eval $CMD || FAILURES="${FAILURES} ${PLATFORM}"
   zip -j release/$ZIP_FILENAME temp/* ./*.dat
@@ -51,7 +59,7 @@ for GOOS in $PLATFORMS_ARM; do
   GOARCH="arm"
   for GOARM in 7 6 5; do
     ZIP_FILENAME="trojan-go-${GOOS}-${GOARCH}v${GOARM}.zip"
-    CMD="CGO_ENABLE=0 GOARM=${GOARM} GOOS=${GOOS} GOARCH=${GOARCH} go build -tags \"full\" -o temp -ldflags \"-s -w\""
+    CMD="CGO_ENABLE=0 GOARM=${GOARM} GOOS=${GOOS} GOARCH=${GOARCH} go build -tags \"full\" -o temp -ldflags \"-s -w ${VAR_SETTING}\""
     echo "${CMD}"
     eval "${CMD}" || FAILURES="${FAILURES} ${GOOS}/${GOARCH}v${GOARM}" 
     zip -j release/$ZIP_FILENAME temp/* ./*.dat
diff --git a/build.sh b/build.sh
index c60a4b3..cd089f6 100755
--- a/build.sh
+++ b/build.sh
@@ -1,3 +1,11 @@
 #!/bin/bash
 
-CGO_ENABLE=0 go build -tags "full" -ldflags="-s -w"
+PACKAGE_NAME="github.com/p4gefau1t/trojan-go"
+VERSION=`git describe`
+COMMIT=`git rev-parse HEAD`
+
+VAR_SETTING=""
+VAR_SETTING="$VAR_SETTING -X $PACKAGE_NAME/constant.Version=$VERSION"
+VAR_SETTING="$VAR_SETTING -X $PACKAGE_NAME/constant.Commit=$COMMIT"
+
+CGO_ENABLE=0 go build -tags "full" -ldflags="-s -w $VAR_SETTING"
diff --git a/common/common.go b/common/common.go
index 69e23a5..eaabb54 100644
--- a/common/common.go
+++ b/common/common.go
@@ -1,31 +1,18 @@
 package common
 
 import (
-	"bufio"
 	"crypto/sha256"
 	"fmt"
-	"io"
 	"log"
 	"os"
 	"path/filepath"
 )
 
-const (
-	Version = "v0.7.2"
-)
-
 type Runnable interface {
 	Run() error
 	Close() error
 }
 
-func NewBufioReadWriter(rw io.ReadWriter) *bufio.ReadWriter {
-	if bufrw, ok := rw.(*bufio.ReadWriter); ok {
-		return bufrw
-	}
-	return bufio.NewReadWriter(bufio.NewReader(rw), bufio.NewWriter(rw))
-}
-
 func SHA224String(password string) string {
 	hash := sha256.New224()
 	hash.Write([]byte(password))
diff --git a/constant/constant.go b/constant/constant.go
new file mode 100644
index 0000000..98759ed
--- /dev/null
+++ b/constant/constant.go
@@ -0,0 +1,6 @@
+package constant
+
+var (
+	Version = "VERSION"
+	Commit  = "COMMIT"
+)
diff --git a/docs/config.toml b/docs/config.toml
index feb345d..40e9744 100755
--- a/docs/config.toml
+++ b/docs/config.toml
@@ -14,9 +14,8 @@ enableMissingTranslationPlaceholders = false
 [params]
 
     # Source Code repository section
-    description = "An unidentifiable mechanism that helps you bypass GFW. "
+    description = "An unidentifiable mechanism that helps you bypass GFW."
     github_repository = "https://github.com/p4gefau1t/trojan-go"
-    version = "0.7.2"
 
     # Documentation repository section
     # documentation repository (set edit link to documentation repository)
diff --git a/proxy/option.go b/proxy/option.go
index 632f08c..a8c6522 100644
--- a/proxy/option.go
+++ b/proxy/option.go
@@ -2,6 +2,7 @@ package proxy
 
 import (
 	"flag"
+	"github.com/p4gefau1t/trojan-go/constant"
 	"github.com/p4gefau1t/trojan-go/log"
 	"github.com/p4gefau1t/trojan-go/option"
 	"io/ioutil"
@@ -24,11 +25,12 @@ func (o *Option) Handle() error {
 	isJSON := false
 	if strings.HasSuffix(*o.path, ".json") {
 		isJSON = true
-	} else if strings.HasSuffix(*o.path, ".yaml") {
+	} else if strings.HasSuffix(*o.path, ".yaml") || strings.HasSuffix(*o.path, ".yml") {
 		isJSON = false
 	} else {
 		log.Fatal("unsupported filename suffix", *o.path, ". use .yaml or .json instead.")
 	}
+	log.Info("trojan-go", constant.Version, "initializing")
 	proxy, err := NewProxyFromConfigData(data, isJSON)
 	if err != nil {
 		log.Fatal(err)
diff --git a/statistic/memory/memory.go b/statistic/memory/memory.go
index 7d24ca5..362c35f 100644
--- a/statistic/memory/memory.go
+++ b/statistic/memory/memory.go
@@ -2,6 +2,7 @@ package memory
 
 import (
 	"context"
+	"github.com/p4gefau1t/trojan-go/log"
 	"sync"
 	"sync/atomic"
 	"time"
@@ -235,6 +236,7 @@ func NewAuthenticator(ctx context.Context) (statistic.Authenticator, error) {
 		hash := common.SHA224String(password)
 		u.AddUser(hash)
 	}
+	log.Debug("memory authenticator created")
 	return u, nil
 }
 
diff --git a/statistic/mysql/mysql.go b/statistic/mysql/mysql.go
index 10c1fcd..3712239 100644
--- a/statistic/mysql/mysql.go
+++ b/statistic/mysql/mysql.go
@@ -36,7 +36,7 @@ func (a *Authenticator) updater() {
 
 			s, err := a.db.Exec("UPDATE `users` SET `upload`=`upload`+?, `download`=`download`+? WHERE `password`=?;", recv, sent, hash)
 			if err != nil {
-				log.Error(common.NewError("Failed to update data to user").Base(err))
+				log.Error(common.NewError("failed to update data to user table").Base(err))
 				continue
 			}
 			if r, err := s.RowsAffected(); err != nil {
@@ -45,12 +45,12 @@ func (a *Authenticator) updater() {
 				}
 			}
 		}
-		log.Info("Buffered data has been written into the database")
+		log.Info("buffered data has been written into the database")
 
 		//update memory
 		rows, err := a.db.Query("SELECT password,quota,download,upload FROM users")
 		if err != nil {
-			log.Error(common.NewError("Failed to pull data from the database").Base(err))
+			log.Error(common.NewError("failed to pull data from the database").Base(err))
 			time.Sleep(a.updateDuration)
 			continue
 		}
@@ -59,7 +59,7 @@ func (a *Authenticator) updater() {
 			var quota, download, upload int64
 			err := rows.Scan(&hash, &quota, &download, &upload)
 			if err != nil {
-				log.Error(common.NewError("Failed to obtain data from the query result").Base(err))
+				log.Error(common.NewError("failed to obtain data from the query result").Base(err))
 				break
 			}
 			if download+upload < quota || quota < 0 {
@@ -107,6 +107,7 @@ func NewAuthenticator(ctx context.Context) (statistic.Authenticator, error) {
 		Authenticator:  memoryAuth.(*memory.Authenticator),
 	}
 	go a.updater()
+	log.Debug("mysql authenticator created")
 	return a, nil
 }
 
diff --git a/statistic/statistics.go b/statistic/statistics.go
index 1d3e65a..97326b8 100644
--- a/statistic/statistics.go
+++ b/statistic/statistics.go
@@ -2,6 +2,7 @@ package statistic
 
 import (
 	"context"
+	"github.com/p4gefau1t/trojan-go/log"
 	"io"
 	"strings"
 
@@ -53,6 +54,7 @@ func RegisterAuthenticatorCreator(name string, creator Creator) {
 func NewAuthenticator(ctx context.Context, name string) (Authenticator, error) {
 	// one authenticator for each context
 	if auth, found := createdAuth[ctx]; found {
+		log.Debug("authenticator has been created:", name)
 		return auth, nil
 	}
 	creator, found := authCreators[strings.ToUpper(name)]
diff --git a/tunnel/trojan/client.go b/tunnel/trojan/client.go
index 75d04a4..e56507c 100644
--- a/tunnel/trojan/client.go
+++ b/tunnel/trojan/client.go
@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"context"
 	"github.com/p4gefau1t/trojan-go/api"
+	"github.com/p4gefau1t/trojan-go/config"
 	"github.com/p4gefau1t/trojan-go/statistic/memory"
 	"github.com/p4gefau1t/trojan-go/tunnel/mux"
 	"net"
@@ -146,7 +147,10 @@ func NewClient(ctx context.Context, client tunnel.Client) (*Client, error) {
 		return nil, err
 	}
 
-	go api.RunService(ctx, Name+"_CLIENT", auth)
+	cfg := config.FromContext(ctx, Name).(*Config)
+	if cfg.API.Enabled {
+		go api.RunService(ctx, Name+"_CLIENT", auth)
+	}
 
 	var user statistic.User
 	for _, u := range auth.ListUsers() {
diff --git a/tunnel/trojan/config.go b/tunnel/trojan/config.go
index b9f806c..b9df543 100644
--- a/tunnel/trojan/config.go
+++ b/tunnel/trojan/config.go
@@ -8,11 +8,16 @@ type Config struct {
 	RemoteHost       string      `json:"remote_addr" yaml:"remote-addr"`
 	RemotePort       int         `json:"remote_port" yaml:"remote-port"`
 	DisableHTTPCheck bool        `json:"disable_http_check" yaml:"disable-http-check"`
-	MySQL            MySQLConfig `json:"mysql" yaml:"mysql"`
+	MySQL            MySQLConfig `json,yaml:"mysql"`
+	API              APIConfig   `json,yaml:"api"`
 }
 
 type MySQLConfig struct {
-	Enabled bool `json:"enabled" yaml:"enabled"`
+	Enabled bool `json,yaml:"enabled"`
+}
+
+type APIConfig struct {
+	Enabled bool `json,yaml:"enabled"`
 }
 
 func init() {
diff --git a/tunnel/trojan/server.go b/tunnel/trojan/server.go
index 4f95ff3..bdd49a4 100644
--- a/tunnel/trojan/server.go
+++ b/tunnel/trojan/server.go
@@ -190,19 +190,27 @@ func (s *Server) AcceptPacket(tunnel.Tunnel) (tunnel.PacketConn, error) {
 	}
 }
 
-func NewServer(ctx context.Context, underlay tunnel.Server) (tunnel.Server, error) {
+func NewServer(ctx context.Context, underlay tunnel.Server) (*Server, error) {
 	cfg := config.FromContext(ctx, Name).(*Config)
 
 	// TODO replace this dirty code
-	auth, err := statistic.NewAuthenticator(ctx, memory.Name)
+	var auth statistic.Authenticator
+	var err error
 	if cfg.MySQL.Enabled {
+		log.Debug("mysql enabled")
 		auth, err = statistic.NewAuthenticator(ctx, mysql.Name)
+	} else {
+		log.Debug("auth by config file")
+		auth, err = statistic.NewAuthenticator(ctx, memory.Name)
 	}
-	go api.RunService(ctx, Name+"_SERVER", auth)
-
 	if err != nil {
-		return nil, common.NewError("failed to create authenticator").Base(err)
+		return nil, common.NewError("trojan failed to create authenticator")
 	}
+
+	if cfg.API.Enabled {
+		go api.RunService(ctx, Name+"_SERVER", auth)
+	}
+
 	redirAddr := tunnel.NewAddressFromHostPort("tcp", cfg.RemoteHost, cfg.RemotePort)
 	ctx, cancel := context.WithCancel(ctx)
 	s := &Server{
diff --git a/version/version.go b/version/version.go
index 3c5b232..9232fb9 100644
--- a/version/version.go
+++ b/version/version.go
@@ -3,6 +3,7 @@ package version
 import (
 	"flag"
 	"fmt"
+	"github.com/p4gefau1t/trojan-go/constant"
 	"github.com/p4gefau1t/trojan-go/option"
 	"runtime"
 
@@ -23,7 +24,11 @@ func (*versionOption) Priority() int {
 
 func (c *versionOption) Handle() error {
 	if *c.flag {
-		fmt.Println("Trojan-Go", common.Version, fmt.Sprintf("(%s %s/%s)", runtime.Version(), runtime.GOOS, runtime.GOARCH))
+		fmt.Println("Trojan-Go", constant.Version)
+		fmt.Println("Go Version:", runtime.Version())
+		fmt.Println("OS/Arch:", runtime.GOOS+"/"+runtime.GOARCH)
+		fmt.Println("Git Commit:", constant.Commit)
+		fmt.Println("")
 		fmt.Println("Developed by PageFault (p4gefau1t)")
 		fmt.Println("Licensed under GNU General Public License version 3")
 		fmt.Println("GitHub Repository:\thttps://github.com/p4gefau1t/trojan-go")