diff --git a/main.go b/main.go
index de7d206..d37a85f 100644
--- a/main.go
+++ b/main.go
@@ -24,11 +24,10 @@ func init() {
 
 var (
 	mp PagesRepository
-)
 
-const (
-	ClientID    = "https://wiki.p83.nl/"
-	RedirectURI = "https://wiki.p83.nl/auth/callback"
+	port               = flag.Int("port", 8080, "listen port")
+	baseurl            = flag.String("baseurl", "", "baseurl")
+	redirectURI string = ""
 )
 
 type Backref struct {
@@ -164,7 +163,7 @@ func (*authHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 			}
 			authURL := sess.AuthorizationEndpoint
 
-			verified, response, err := indieauth.VerifyAuthCode(ClientID, code, RedirectURI, authURL)
+			verified, response, err := indieauth.VerifyAuthCode(*baseurl, code, redirectURI, authURL)
 			if err != nil {
 				http.Error(w, err.Error(), 500)
 				return
@@ -220,11 +219,11 @@ func (*authHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 			sess.AuthorizationEndpoint = authURL.String()
 			sess.Me = urlString
 			sess.LoggedIn = false
-			sess.RedirectURI = RedirectURI
+			sess.RedirectURI = redirectURI
 			sess.NextURI = "/"
 			sess.State = state
 
-			newURL := indieauth.CreateAuthenticationURL(*authURL, urlString, ClientID, RedirectURI, state)
+			newURL := indieauth.CreateAuthenticationURL(*authURL, urlString, *baseurl, redirectURI, state)
 
 			http.Redirect(w, r, newURL, 302)
 			return
@@ -298,8 +297,7 @@ func (h *historyHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 }
 
 func getPageBase() pageBaseInfo {
-	clientID := ClientID
-	redirectURI := RedirectURI
+	clientID := *baseurl
 
 	pageBase := pageBaseInfo{
 		BaseURL:     clientID,
@@ -409,12 +407,12 @@ func (h *editHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	pageBase := getPageBase()
 	data := editPage{
 		pageBaseInfo: pageBase,
-		Session:  sess,
-		Title:    cleanTitle(page),
-		Content:  pageText,
-		Editor:   editor,
-		Name:     page,
-		Backrefs: mpPage.Refs,
+		Session:      sess,
+		Title:        cleanTitle(page),
+		Content:      pageText,
+		Editor:       editor,
+		Name:         page,
+		Backrefs:     mpPage.Refs,
 	}
 
 	t, err := template.ParseFiles("templates/layout.html", "templates/edit.html")
@@ -512,11 +510,11 @@ func (h *indexHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	pageBase := getPageBase()
 	data := indexPage{
 		pageBaseInfo: pageBase,
-		Session:  sess,
-		Title:    cleanTitle(page),
-		Content:  template.HTML(pageText),
-		Name:     page,
-		Backrefs: mpPage.Refs,
+		Session:      sess,
+		Title:        cleanTitle(page),
+		Content:      template.HTML(pageText),
+		Name:         page,
+		Backrefs:     mpPage.Refs,
 	}
 
 	t, err := template.ParseFiles("templates/layout.html", "templates/view.html")
@@ -584,10 +582,10 @@ func (h *recentHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	pageBase := getPageBase()
 	err = t.Execute(w, recentPage{
 		pageBaseInfo: pageBase,
-		Session: sess,
-		Title:   "Recent changes",
-		Name:    "Recent changes",
-		Recent:  changes,
+		Session:      sess,
+		Title:        "Recent changes",
+		Name:         "Recent changes",
+		Recent:       changes,
 	})
 	if err != nil {
 		http.Error(w, err.Error(), 500)
@@ -612,10 +610,11 @@ type LinkResponse struct {
 }
 
 func main() {
-	var port int
-	flag.IntVar(&port, "port", 8080, "http port")
 	flag.Parse()
 
+	*baseurl = strings.TrimRight(*baseurl, "/") + "/"
+	redirectURI = fmt.Sprintf("%sauth/callback", *baseurl)
+
 	mp = NewFilePages("data")
 
 	http.Handle("/auth/", &authHandler{})
@@ -684,6 +683,6 @@ func main() {
 	http.Handle("/recent/", &recentHandler{})
 	http.Handle("/", &indexHandler{})
 
-	fmt.Printf("Running on port %d\n", port)
-	log.Fatal(http.ListenAndServe(fmt.Sprintf(":%d", port), nil))
+	fmt.Printf("Running on port %d\n", *port)
+	log.Fatal(http.ListenAndServe(fmt.Sprintf(":%d", *port), nil))
 }