diff --git a/config.sample.php b/config.sample.php
index 43a3370..9e43883 100644
--- a/config.sample.php
+++ b/config.sample.php
@@ -14,7 +14,17 @@ $config = [
     // optional: Do you have a place where howTo's are located? If not leave this value out
     "howToURL" => "https://my-url-for-storing-howTos.net",
 
+    // set the mode of operation. Basically this defines where the data is stored:
+    // - synapse (using the register endpoint - so no further auth config necessary
+    // - local (recommended; using a table in the database to store credentials;
+    //   synapse has to be configured to use that)
+    "operationMode" => "local",
+
+    // This setting is only required for operationMode = synapse
+    "registration_shared_secret" => "SOME_SECRET_KEY_FROM_HOMESERVER_CONFIG"
+
     // When you want to collect the password on registration set this to true
+    // only evaluated when operationMode = local
     "getPasswordOnRegistration" => false,
 
     // default language: one of [ en-gb | de-de ]
diff --git a/database.php b/database.php
index d654c66..fef634c 100644
--- a/database.php
+++ b/database.php
@@ -241,7 +241,7 @@ class mxDatabase {
         $res = $this->db->query($sql);
 
         if ($res->fetchColumn() > 0) {
-            $sql = "SELECT first_name, last_name, note, email, admin_token FROM registrations "
+            $sql = "SELECT first_name, last_name, note, email, username, admin_token FROM registrations "
                     . " WHERE verify_token = '" . $verify_token . "'"
                     . " AND state = " . RegisterState::PendingEmailVerify . " LIMIT 1;";
             foreach ($this->db->query($sql) as $row) {
diff --git a/internal/directory_search.php b/internal/directory_search.php
index d6419cd..2149a82 100644
--- a/internal/directory_search.php
+++ b/internal/directory_search.php
@@ -46,5 +46,5 @@ try {
     error_log("failed with error: " . $e->getMessage());
     $response["error"] = $e->getMessage();
 }
-print (json_encode($response, JSON_PRETTY_PRINT) . "\n");
+print (json_encode($response, JSON_PRETTY_PRINT));
 ?>
diff --git a/internal/identity_bulk.php b/internal/identity_bulk.php
index 120871e..8c87e12 100644
--- a/internal/identity_bulk.php
+++ b/internal/identity_bulk.php
@@ -66,5 +66,5 @@ try {
     error_log("ídentity_bulk failed with error: " . $e->getMessage());
     $response["error"] = $e->getMessage();
 }
-print (json_encode($response, JSON_PRETTY_PRINT) . "\n");
+print (json_encode($response, JSON_PRETTY_PRINT));
 ?>
diff --git a/internal/identity_single.php b/internal/identity_single.php
index 8a317d9..fde3dd8 100644
--- a/internal/identity_single.php
+++ b/internal/identity_single.php
@@ -61,5 +61,5 @@ try {
         "error" => $e->getMessage()
     ];
 }
-print (json_encode($response, JSON_PRETTY_PRINT) . "\n");
+print (json_encode($response, JSON_PRETTY_PRINT));
 ?>
diff --git a/internal/login.php b/internal/login.php
index 57d7685..9f44dbe 100644
--- a/internal/login.php
+++ b/internal/login.php
@@ -108,5 +108,5 @@ try {
     error_log("Auth failed with error: " . $e->getMessage());
     $response["auth"]["error"] = $e->getMessage();
 }
-print (json_encode($response, JSON_PRETTY_PRINT) . "\n");
+print (json_encode($response, JSON_PRETTY_PRINT));
 ?>
diff --git a/lang/lang.de-de.php b/lang/lang.de-de.php
index ded1271..d059bf9 100644
--- a/lang/lang.de-de.php
+++ b/lang/lang.de-de.php
@@ -1,4 +1,5 @@
 <?php
+
 /**
  * Copyright 2018 Matthias Kesler
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -53,7 +54,8 @@ $language = array(
     "ADMIN_REGISTER_ACCEPTED_BODY" => "Die Registrierungsanfrage wurde akzeptiert. Der Nutzer wurde per Mail informiert.",
     "ADMIN_REGISTER_DECLINED_BODY" => "Die Registrierungsanfrage wurde angelehnt. Der Nutzer wurde per Mail informiert.",
     "JUMP_TO_HOMEPAGE" => "Zur Startseite",
-    "TOPIC_PLEASE_REGISTER" => "Bitte für @homeserver registrieren<small>2-Schritt-Registrierung</small>",
+    "TOPIC_PLEASE_REGISTER" => "Bitte für @homeserver registrieren",
+    "TOPIC_PLEASE_REGISTER_NOTE" => "2-Schritt-Registrierung",
     "NOTE_FOR_REGISTRATION" => "@homeserver ist ein geschlossenes Chat-Netzwerk in dem jeder Nutzer bestätigt werden muss.<br />
         Du bekommst eine E-Mail wenn jemand deine Mitgliedschaft bestätigt hat. An diese wird auch dein initiales Passwort gesendet.
         Hinterlasse also bitte einen Hinweis zu dir (den nur die Administratoren sehen werden).<br />
diff --git a/mail_templates.php b/mail_templates.php
index b3c9c23..3d62e3c 100644
--- a/mail_templates.php
+++ b/mail_templates.php
@@ -24,6 +24,7 @@ if (!file_exists($lang_file)) {
     error_log("Mail templates for '" . $lang . "' not found. Fallback to 'de-de'");
     $lang = "de-de";
 }
+$lang_file = dirname(__FILE__) . "/lang/mail." . $lang . ".php";
 require_once($lang_file);
 unset($lang_file);
 ?>
diff --git a/public/index.php b/public/index.php
index 12fac63..df9db26 100644
--- a/public/index.php
+++ b/public/index.php
@@ -13,6 +13,12 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+// enforce admin via https
+if (!isset($_SERVER['HTTPS'])) {
+    header('Location: https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'], true, 301);
+    exit();
+}
+
 require_once "../language.php";
 if (!file_exists("../config.php")) {
     print($language["NO_CONFIGURATION"]);
@@ -20,12 +26,18 @@ if (!file_exists("../config.php")) {
 }
 require_once "../config.php";
 
-// enforce admin via https
-if (!isset($_SERVER['HTTPS'])) {
-    header('Location: https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'], true, 301);
-    exit();
+// this values will not be used when using the register operation type
+$storeFirstLastName = false;
+if (isset($config["operationMode"]) && $config["operationMode"] === "local") {
+    $storeFirstLastName = true;
 }
 
+// currently the case to store the password on our own is the only supported one
+$storePassword = false;
+if (isset($config["getPasswordOnRegistration"]) && $config["getPasswordOnRegistration"] &&
+        isset($config["operationMode"]) && $config["operationMode"] === "synapse") {
+    $storePassword = true;
+}
 session_start();
 
 if ($_SERVER["REQUEST_METHOD"] == "POST") {
@@ -53,17 +65,22 @@ if ($_SERVER["REQUEST_METHOD"] == "POST") {
         if (!isset($_POST["email"]) || !filter_var($_POST["email"], FILTER_VALIDATE_EMAIL)) {
             throw new Exception("EMAIL_INVALID_FORMAT");
         }
-        if (isset($_POST["first_name"]) && !preg_match("/[A-Z][a-z]+/", $_POST["first_name"])) {
-            throw new Exception("FIRSTNAME_INVALID_FORMAT");
-        }
-        if (isset($_POST["last_name"]) && !preg_match("/[A-Z][a-z]+/", $_POST["last_name"])) {
-            throw new Exception("SIRNAME_INVALID_FORMAT");
+        if ($storeFirstLastName) {
+            // only require first_name and last_name when we will evaluate them
+            if (!isset($_POST["first_name"]) || !preg_match("/[A-Z][a-z]+/", $_POST["first_name"])) {
+                throw new Exception("FIRSTNAME_INVALID_FORMAT");
+            }
+            if (!isset($_POST["last_name"]) || !preg_match("/[A-Z][a-z]+/", $_POST["last_name"])) {
+                throw new Exception("SIRNAME_INVALID_FORMAT");
+            }
+            $first_name = filter_var($_POST["first_name"], FILTER_SANITIZE_STRING);
+            $last_name = filter_var($_POST["last_name"], FILTER_SANITIZE_STRING);
+        } else {
+            $first_name = $last_name = "";
         }
 
-        $first_name = filter_var($_POST["first_name"], FILTER_SANITIZE_STRING);
-        $last_name = filter_var($_POST["last_name"], FILTER_SANITIZE_STRING);
         $username = filter_var($_POST["username"], FILTER_SANITIZE_STRING);
-        if (isset($_POST["password"])) {
+        if ($storePassword && isset($_POST["password"])) {
             $password = filter_var($_POST["password"], FILTER_SANITIZE_STRING);
         }
         $note = filter_var($_POST["note"], FILTER_SANITIZE_STRING);
@@ -81,7 +98,7 @@ if ($_SERVER["REQUEST_METHOD"] == "POST") {
         $verify_url = $config["webroot"] . "/verify.php?t=" . $verify_token;
         require_once "../mail_templates.php";
         $success = send_mail_pending_verification(
-                $config["homeserver"], $first_name . " " . $last_name, $email, $verify_url);
+                $config["homeserver"], $storeFirstLastName ? $first_name . " " . $last_name : $username, $email, $verify_url);
 
         $mx_db->setRegistrationStateVerify(
                 ($success ? RegisterState::PendingEmailVerify : RegisterState::PendingEmailSend), $verify_token);
@@ -105,7 +122,7 @@ if ($_SERVER["REQUEST_METHOD"] == "POST") {
 } else {
     $_SESSION["token"] = bin2hex(random_bytes(16));
     ?>
-    <title>Registriere dich für <?php echo $config["homeserver"]; ?></title>
+    <title><?php echo strtr($language["TOPIC_PLEASE_REGISTER"], [ "@homeserver" => $config["homeserver"] ]); ?></title>
     <link href="//netdna.bootstrapcdn.com/bootstrap/3.1.0/css/bootstrap.min.css" rel="stylesheet">
     <style>
         body{
@@ -129,10 +146,12 @@ if ($_SERVER["REQUEST_METHOD"] == "POST") {
             <div class="col-xs-12 col-sm-8 col-md-4 col-sm-offset-2 col-md-offset-4">
                 <div class="panel panel-default">
                     <div class="panel-heading">
-                        <h3 class="panel-title"><?php echo strtr($language["TOPIC_PLEASE_REGISTER"], [ "@homeserver" => $config["homeserver"] ]); ?></h3>
+                        <h3 class="panel-title"><?php echo strtr($language["TOPIC_PLEASE_REGISTER"], [ "@homeserver" => $config["homeserver"] ])
+                                . "<small>" . $language["TOPIC_PLEASE_REGISTER_NOTE"] . "</small>"; ?></h3>
                     </div>
                     <div class="panel-body">
                         <form name="regForm" role="form" action="index.php" method="post">
+<?php if ($storeFirstLastName) { ?>
                             <div class="row">
                                 <div class="col-xs-6 col-sm-6 col-md-6">
                                     <div class="form-group">
@@ -147,6 +166,7 @@ if ($_SERVER["REQUEST_METHOD"] == "POST") {
                                     </div>
                                 </div>
                             </div>
+<?php } ?>
 
                             <div class="form-group">
                                 <input type="email" name="email" id="email" class="form-control input-sm" placeholder="<?php echo $language["EMAIL_ADDRESS"]; ?>" required>
@@ -160,7 +180,7 @@ if ($_SERVER["REQUEST_METHOD"] == "POST") {
                                 <input type="text" name="username" id="username" class="form-control input-sm"
                                        placeholder="<?php echo $language["USERNAME"]; ?>" pattern="[a-z1-9]{3,20}" required>
                             </div>
-                            <?php if (isset($config["getPasswordOnRegistration"]) && $config["getPasswordOnRegistration"]) { ?>
+<?php if ($storePassword) { ?>
                                 <div class="row">
                                     <div class="col-xs-6 col-sm-6 col-md-6">
                                         <div class="form-group">
@@ -173,7 +193,7 @@ if ($_SERVER["REQUEST_METHOD"] == "POST") {
                                         </div>
                                     </div>
                                 </div>
-                            <?php } ?>
+<?php } ?>
                             <input type="hidden" name="token" id="token" value="<?php echo $_SESSION["token"]; ?>">
                             <input type="submit" value="<?php echo $language["REGISTER"]; ?>" class="btn btn-info btn-block">
 
@@ -189,20 +209,6 @@ if ($_SERVER["REQUEST_METHOD"] == "POST") {
         </div>
     </div>
     <script type="text/javascript">
-        var first_name = document.getElementById("first_name");
-        first_name.oninvalid = function (event) {
-            event.target.setCustomValidity("<?php echo $language["FIRSTNAME_INVALID_FORMAT"]; ?>");
-        }
-        first_name.onkeyup = function (event) {
-            event.target.setCustomValidity("");
-        }
-        var last_name = document.getElementById("last_name");
-        last_name.oninvalid = function (event) {
-            event.target.setCustomValidity("<?php echo $language["SIRNAME_INVALID_FORMAT"]; ?>");
-        }
-        last_name.onkeyup = function (event) {
-            event.target.setCustomValidity("");
-        }
         var user_name = document.getElementById("username");
         user_name.oninvalid = function (event) {
             event.target.setCustomValidity("<?php echo $language["USERNAME_LENGTH_INVALID"]; ?>");
@@ -210,7 +216,22 @@ if ($_SERVER["REQUEST_METHOD"] == "POST") {
         user_name.onkeyup = function (event) {
             event.target.setCustomValidity("");
         }
-<?php if (isset($config["getPasswordOnRegistration"]) && $config["getPasswordOnRegistration"]) { ?>
+<?php if ($storeFirstLastName) { ?>
+            var first_name = document.getElementById("first_name");
+            first_name.oninvalid = function (event) {
+                event.target.setCustomValidity("<?php echo $language["FIRSTNAME_INVALID_FORMAT"]; ?>");
+            }
+            first_name.onkeyup = function (event) {
+                event.target.setCustomValidity("");
+            }
+            var last_name = document.getElementById("last_name");
+            last_name.oninvalid = function (event) {
+                event.target.setCustomValidity("<?php echo $language["SIRNAME_INVALID_FORMAT"]; ?>");
+            }
+            last_name.onkeyup = function (event) {
+                event.target.setCustomValidity("");
+            }
+<?php } if ($storePassword) { ?>
             var password = document.getElementById("password")
                     , confirm_password = document.getElementById("password_confirm");
             function validatePassword() {
@@ -225,5 +246,4 @@ if ($_SERVER["REQUEST_METHOD"] == "POST") {
 <?php } ?>
     </script>
 <?php } ?>
-    </body>
-</html>
+</body></html>
\ No newline at end of file
diff --git a/public/verify.php b/public/verify.php
index c40f0ad..35b9af0 100644
--- a/public/verify.php
+++ b/public/verify.php
@@ -46,6 +46,7 @@ try {
     }
     $first_name = $user["first_name"];
     $last_name = $user["last_name"];
+    $username = $user["username"];
     $note = $user["note"];
     $email = $user["email"];
     $admin_token = $user["admin_token"];
@@ -55,13 +56,13 @@ try {
     $mxConn = new MatrixConnection($config["homeserver"], $config["access_token"]);
     $mxMsg = new MatrixMessage();
     $mxMsg->set_body(strtr($language["MSG_USER_WANTS_REGISTER"], [
-                "@name" => $first_name . ' ' . $last_name,
+                "@name" => (strlen($first_name . $last_name) > 0 ? $first_name . " " . $last_name : $username),
                 "@note" => $note,
                 "@adminUrl" => $adminUrl
             ]));
     if (isset($language["MSG_USER_WANTS_REGISTER_FORMATTED"])) {
         $mxMsg->set_formatted_body(strtr($language["MSG_USER_WANTS_REGISTER_FORMATTED"], [
-                "@name" => $first_name . ' ' . $last_name,
+                "@name" => (strlen($first_name . $last_name) > 0 ? $first_name . " " . $last_name : $username),
                 "@note" => $note,
                 "@adminUrl" => $adminUrl
             ]));
diff --git a/public/verify_admin.php b/public/verify_admin.php
index 0cdb56b..9e98375 100644
--- a/public/verify_admin.php
+++ b/public/verify_admin.php
@@ -70,11 +70,30 @@ try {
         require_once("../MatrixConnection.php");
         $mxConn = new MatrixConnection($config["homeserver"], $config["access_token"]);
 
-        // generate a password with 8 characters
-        $password = $mx_db->addUser($first_name, $last_name, $username, $email);
+        $password = NULL;
+        switch ($config["operationMode"]) {
+            case "synapse":
+                // register with registration_shared_secret
+                // generate a password with 10 characters
+                $password = bin2hex(openssl_random_pseudo_bytes(5));
+                $res = $mxConn->register($username, $password, $config["registration_shared_secret"]);
+                if (!$res) {
+                    // something went wrong while registering
+                    $password = NULL;
+                }
+                break;
+            case "local":
+                // register by adding a user to the local database
+                $password = $mx_db->addUser($first_name, $last_name, $username, $email);
+                break;
+            default:
+                throw new Exception("Unknown operationMode");
+        }
         if ($password != NULL) {
             // send registration_success
-            $res = send_mail_registration_success($config["homeserver"], $first_name . " " . $last_name, $email, $username, $password, $config["howToURL"]);
+            $res = send_mail_registration_success(
+                    $config["homeserver"], $first_name . " " . $last_name, $email, $username, $password, $config["howToURL"]
+                );
             if ($res) {
                 $mx_db->setRegistrationStateAdmin(RegisterState::AllDone, $token);
             } else {
@@ -84,7 +103,9 @@ try {
             send_mail_registration_allowed_but_failed($config["homeserver"], $first_name . " " . $last_name, $email);
             $mxMsg = new MatrixMessage();
             $mxMsg->set_type("m.text");
-            $mxMsg->set_body(strtr($language["REGISTRATION_FAILED_FOR"], [ "@name" => $first_name . " " . $last_name]));
+            $mxMsg->set_body(strtr($language["REGISTRATION_FAILED_FOR"], [
+                "@name" => strlen($first_name . $last_name) > 0 ? $first_name . " " . $last_name : $username,
+            ]));
             $mxConn->send($config["register_room"], $mxMsg);
             throw new Exception("REGISTRATION_FAILED");
         }
@@ -95,7 +116,9 @@ try {
         print("<p>" . $language["ADMIN_REGISTER_ACCEPTED_BODY"] . "</p>");
     } elseif ($action == RegisterState::RegistrationDeclined) {
         $mx_db->setRegistrationStateAdmin(RegisterState::RegistrationDeclined, $token);
-        send_mail_registration_decline($config["homeserver"], $first_name . " " . $last_name, $email, $decline_reason);
+        send_mail_registration_decline(
+                $config["homeserver"], strlen($first_name . $last_name) > 0 ? $first_name . " " . $last_name : $username, $email, $decline_reason
+        );
         print("<title>" . $language["ADMIN_VERIFY_SITE_TITLE"] . "</title>");
         print("</head><body>");
         print("<h1>" . $language["ADMIN_VERIFY_SITE_TITLE"] . "</h1>");
@@ -131,21 +154,24 @@ try {
                         </div>
                         <div class="panel-body">
                             <form name="appForm" role="form" action="verify_admin.php" method="GET">
-                                <div class="row">
-                                    <div class="col-xs-6 col-sm-6 col-md-6">
-                                        <div class="form-group">
-                                            <input type="text" id="first_name" class="form-control input-sm"
-                                                   value="<?php echo $first_name; ?>" disabled=true>
+<?php if (isset($config["operationMode"]) && $config["operationMode"] === "local") {
+    // this values will not be used when using the register operation type 
+    ?>
+                                    <div class="row">
+                                        <div class="col-xs-6 col-sm-6 col-md-6">
+                                            <div class="form-group">
+                                                <input type="text" id="first_name" class="form-control input-sm"
+                                                       value="<?php echo $first_name; ?>" disabled=true>
+                                            </div>
+                                        </div>
+                                        <div class="col-xs-6 col-sm-6 col-md-6">
+                                            <div class="form-group">
+                                                <input type="text" id="last_name" class="form-control input-sm"
+                                                       value="<?php echo $last_name; ?>" disabled=true>
+                                            </div>
                                         </div>
                                     </div>
-                                    <div class="col-xs-6 col-sm-6 col-md-6">
-                                        <div class="form-group">
-                                            <input type="text" id="last_name" class="form-control input-sm"
-                                                   value="<?php echo $last_name; ?>" disabled=true>
-                                        </div>
-                                    </div>
-                                </div>
-
+<?php } ?>
                                 <div class="form-group">
                                     <input type="text" id="note" class="form-control input-sm" value="<?php echo $note; ?>" disabled=true>
                                 </div>
@@ -157,7 +183,6 @@ try {
                                 <input type="hidden" name="t" id="token" value="<?php echo $token; ?>">
                                 <input type="submit" name="allow" value="<?php echo $language["ACCEPT"]; ?>" class="btn btn-info btn-block">
                                 <input type="submit" name="deny" value="<?php echo $language["DECLINE"]; ?>" class="btn btn-info btn-block">
-
                             </form>
                         </div>
                     </div>