diff --git a/api.go b/api.go
index df91853..90fa4aa 100644
--- a/api.go
+++ b/api.go
@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"io/ioutil"
 	"net/http"
+	"os"
 
 	"kumoly.io/tools/configui/configui"
 )
@@ -11,8 +12,7 @@ import (
 func ListFiles(w http.ResponseWriter, r *http.Request) {
 	data, err := json.Marshal(files)
 	if err != nil {
-		AbortError(w, err)
-		return
+		panic(err)
 	}
 	w.Write(data)
 }
@@ -26,8 +26,7 @@ func GetFile(w http.ResponseWriter, r *http.Request) {
 	}
 	data, err := file.Read()
 	if err != nil {
-		AbortError(w, err)
-		return
+		panic(err)
 	}
 	response, err := json.Marshal(map[string]string{
 		"path":   file.Path,
@@ -36,8 +35,7 @@ func GetFile(w http.ResponseWriter, r *http.Request) {
 		"data":   string(data),
 	})
 	if err != nil {
-		AbortError(w, err)
-		return
+		panic(err)
 	}
 	w.Header().Set("Content-Type", "application/json")
 	w.Write(response)
@@ -47,13 +45,11 @@ func PostFile(w http.ResponseWriter, r *http.Request) {
 	data, err := ioutil.ReadAll(r.Body)
 	r.Body.Close()
 	if err != nil {
-		AbortError(w, err)
-		return
+		panic(err)
 	}
 	f := configui.File{}
 	if err := json.Unmarshal(data, &f); err != nil {
-		AbortError(w, err)
-		return
+		panic(err)
 	}
 	file, ok := files[f.Alias]
 	if !ok {
@@ -61,8 +57,7 @@ func PostFile(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	if err := file.Write([]byte(f.Data)); err != nil {
-		AbortError(w, err)
-		return
+		panic(err)
 	}
 	w.Write([]byte("ok"))
 }
@@ -76,8 +71,7 @@ func Apply(w http.ResponseWriter, r *http.Request) {
 	}
 	result, err := file.Do()
 	if err != nil {
-		AbortError(w, err)
-		return
+		panic(err)
 	}
 	w.Write([]byte(result))
 }
@@ -93,19 +87,23 @@ func Download(w http.ResponseWriter, r *http.Request) {
 
 func LoadConfig(w http.ResponseWriter, r *http.Request) {
 	if flagNoReconfig {
-		AbortError(w, "system reconfig is disabled")
-		return
+		panic("system reconfig is disabled")
 	}
 	data, err := ioutil.ReadAll(r.Body)
 	r.Body.Close()
 	if err != nil {
-		AbortError(w, err)
-		return
+		panic(err)
 	}
 	ftmp, err := configui.ReadConfig(string(data))
 	if err != nil {
-		AbortError(w, err)
-		return
+		panic(err)
+	}
+	if flagConfigPath != "" {
+		info, err := os.Stat(flagConfigPath)
+		if err != nil {
+			panic(err)
+		}
+		os.WriteFile(flagConfigPath, data, info.Mode())
 	}
 	files = configui.GetFileMap(ftmp)
 	w.Write([]byte("ok"))
@@ -114,8 +112,7 @@ func LoadConfig(w http.ResponseWriter, r *http.Request) {
 func getConfigHandler(w http.ResponseWriter, r *http.Request) {
 	data, err := GetConfig()
 	if err != nil {
-		AbortError(w, err)
-		return
+		panic(err)
 	}
 	w.Write(data)
 }
diff --git a/configui/file.go b/configui/file.go
index 6e2ffb2..ba8da5a 100644
--- a/configui/file.go
+++ b/configui/file.go
@@ -18,6 +18,7 @@ type File struct {
 	Alias  string `json:"name"`
 	Action string `json:"action"`
 	RO     bool   `json:"ro"`
+	Lang   string `json:"lang"`
 
 	// used for parsing post data
 	Data string `json:"data"`
diff --git a/netutil.go b/netutil.go
index ef4b12c..3727b76 100644
--- a/netutil.go
+++ b/netutil.go
@@ -54,7 +54,7 @@ func AbortError(w http.ResponseWriter, err interface{}) (int, error) {
 func Catch(rw *ResponseWriter, r *http.Request) {
 	ex := recover()
 	if ex != nil {
-		AbortError(rw, r)
+		AbortError(rw, ex)
 		log.Printf("%s %s %d %s %s\n", GetIP(r), r.Method, rw.StatueCode, r.URL, r.Header.Get("User-Agent"))
 	}
 }
@@ -102,8 +102,7 @@ func Parse(w http.ResponseWriter, name string, data interface{}) error {
 	buf := &bytes.Buffer{}
 	err := tmpl.ExecuteTemplate(buf, "home", data)
 	if err != nil {
-		AbortError(w, err)
-		return err
+		panic(err)
 	}
 	_, err = w.Write(buf.Bytes())
 	return err
diff --git a/route.go b/route.go
index 7320b04..1c0b9ae 100644
--- a/route.go
+++ b/route.go
@@ -75,11 +75,15 @@ func setRoutes(mux *http.ServeMux) {
 			tmp, err = file.Read()
 			data.File.Action = file.Action
 			data.File.Alias = file.Alias
-			ext := strings.TrimPrefix(filepath.Ext(file.Path), ".")
-			if ext2mode[ext] != "" {
-				ext = ext2mode[ext]
+			if file.Lang != "" {
+				data.Editor.Lang = file.Lang
+			} else {
+				ext := strings.TrimPrefix(filepath.Ext(file.Path), ".")
+				if ext2mode[ext] != "" {
+					ext = ext2mode[ext]
+				}
+				data.Editor.Lang = ext
 			}
-			data.Editor.Lang = ext
 			data.File.RO = file.RO
 			data.File.Path = file.Path
 		}