diff --git a/chat.php b/chat.php
index 135d717..faac59e 100644
--- a/chat.php
+++ b/chat.php
@@ -1,14 +1,16 @@
 <?php
 
-var_dump ($_POST);
-
 require_once './modules/chat.mod.php';
 
 
-$chat = new Chat;
-
 $user_id = $_GET['id'];
+$pass = $_GET['pass'];
 $chat_message = $_GET['text'];
 
-$chat -> send ($user_id, $chat_message);
+
+
+$chat = new Chat;
+$chat -> user_id = $user_id;
+$chat -> text = $chat_message;
+$chat -> insert ();
 
diff --git a/migrations/2023_07_01_080700_add_pass_to_chats_table.sql b/migrations/2023_07_01_080700_add_pass_to_chats_table.sql
new file mode 100644
index 0000000..f0272f4
--- /dev/null
+++ b/migrations/2023_07_01_080700_add_pass_to_chats_table.sql
@@ -0,0 +1 @@
+ALTER TABLE `users` ADD `pass` VARCHAR(64) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL COMMENT 'パスワード' AFTER `name`;
diff --git a/modules/chat.mod.php b/modules/chat.mod.php
index 5318026..c478338 100644
--- a/modules/chat.mod.php
+++ b/modules/chat.mod.php
@@ -5,6 +5,10 @@ Chat
 {
   private $db;
 
+  private $id;
+  var     $user_id;
+  var     $pass;
+
   function
   __construct ()
   {
@@ -20,9 +24,7 @@ Chat
   }
 
   function
-  send (
-      int     $user_id,
-      string  $text):
+  insert ():
   void
   {
     $sql = "
@@ -32,8 +34,8 @@ Chat
             text)
           VALUES
             (
-              $user_id,
-              '$text')";
+              {$this -> user_id},
+              '{$this -> text}')";
     $this -> db -> query ($sql) or die ("db_insert error $sql");
   }
 }
diff --git a/modules/user.mod.php b/modules/user.mod.php
new file mode 100644
index 0000000..ca998f0
--- /dev/null
+++ b/modules/user.mod.php
@@ -0,0 +1,50 @@
+<?php
+
+class
+User
+{
+  private $db;
+
+  private $id;
+  var     $name;
+  var     $pass;
+
+  function
+  __construct ()
+  {
+    $config = include ('./config.php');
+
+    $db_host = $config['host'];
+    $db_port = $config['port'];
+    $db_user = $config['user'];
+    $db_pass = $config['pass'];
+
+    $this -> db = new mysqli ($db_host, $db_user, $db_pass, 'goatoh_training',
+                              $db_port);
+  }
+
+  public static function
+  find (
+      int $id):
+  Self
+  {
+    $sql = "
+        SELECT
+          *
+        FROM
+          user
+        WHERE
+          id = $id";
+    $result = $this -> db -> query ($sql) or die ("db_select error $sql");
+
+    $row = $this -> db -> fetch_array ($result);
+
+    $self = new Self;
+    $self -> id = $id;
+    $self -> name = $row['name'];
+    $self -> pass = $row['pass'];
+
+    return $self;
+  }
+}
+