diff --git a/source/lib/SihnonFramework/Auth/Plugin/FlatFile.class.php b/source/lib/SihnonFramework/Auth/Plugin/FlatFile.class.php
new file mode 100644
index 0000000..7480d9e
--- /dev/null
+++ b/source/lib/SihnonFramework/Auth/Plugin/FlatFile.class.php
@@ -0,0 +1,71 @@
+<?php
+
+class SihnonFramework_Auth_Plugin_FlatFile
+    extends    Sihnon_PluginBase
+    implements Sihnon_Auth_IPlugin,
+    Sihnon_Auth_IUpdateable,
+    Sihnon_Auth_IPermissionable {
+
+    protected $config;
+    
+    protected function __construct($config) {
+        $this->config = $config;
+    }
+    
+    /*
+     * IPlugin methods
+    */
+    
+    public static function create(SihnonFramework_Config $config) {
+        return new self($config);
+    }
+    
+    public function userExists($username) {
+        return Sihnon_Auth_Plugin_FlatFile_User::exists($username);
+    }
+    
+    public function listUsers() {
+        return Sihnon_Auth_Plugin_FlatFile_User::all();
+    }
+    
+    public function authenticate($username, $password) {
+        $user = Sihnon_Auth_Plugin_FlatFile_User::load($username);
+    
+        if ( ! $user->checkPassword($password)) {
+            throw new Sihnon_Exception_IncorrectPassword();
+        }
+    
+        return $user;
+    }
+    
+    public function authenticateSession($username) {
+        return Sihnon_Auth_Plugin_FlatFile_User::load($username);
+    }
+    
+    /*
+     * IUpdateable methods
+    */
+    
+    public function addUser($username, $password) {
+        return Sihnon_Auth_Plugin_Database_User::add($username, $password);
+    }
+    
+    public function removeUser(Sihnon_Auth_IUser $user) {
+        $user->delete();
+    }
+    
+    public function changePassword(Sihnon_Auth_IUser $user, $new_password) {
+        $user->changePassword($new_password);
+    }
+    
+    /*
+     * IPermissionable methods
+    */
+    
+    public function isAdministrator(Sihnon_Auth_IUser $user) {
+        return $user->isAdministrator();
+    }
+
+}
+
+?>
\ No newline at end of file
diff --git a/source/lib/SihnonFramework/Auth/Plugin/FlatFile/User.class.php b/source/lib/SihnonFramework/Auth/Plugin/FlatFile/User.class.php
new file mode 100644
index 0000000..4f5a80f
--- /dev/null
+++ b/source/lib/SihnonFramework/Auth/Plugin/FlatFile/User.class.php
@@ -0,0 +1,35 @@
+<?php
+
+class SihnonFramework_Auth_Plugin_FlatFile_User implements Sihnon_Auth_IUser {
+    
+    public static function exists($username) {
+        throw new SihnonFramework_Exception_NotImplemented();
+    }
+    
+    public static function load($username) {
+        throw new SihnonFramework_Exception_NotImplemented();
+    }
+
+    public static function add($username, $password) {
+        throw new SihnonFramework_Exception_NotImplemented();
+    }
+    
+    public function username() {
+        return $this->username;
+    }
+    
+    public function checkPassword($password) {
+        return ($this->password == sha1($password));
+    }
+    
+    public function changePassword($new_password) {
+        throw new SihnonFramework_Exception_NotImplemented();
+    }
+    
+    public function isAdministrator() {
+        throw new SihnonFramework_Exception_NotImplemented();
+    }
+    
+}
+
+?>
\ No newline at end of file