diff --git a/init.php b/init.php
index a0a02122..da96770f 100644
--- a/init.php
+++ b/init.php
@@ -52,3 +52,7 @@ download('http://raw.github.com/aehlke/tag-it/master/js/tag-it.min.js', $libPath
 //fonts
 download('http://googlefontdirectory.googlecode.com/hg/apache/droidsans/DroidSans.ttf', $fontsPath . 'DroidSans.ttf');
 download('http://googlefontdirectory.googlecode.com/hg/apache/droidsans/DroidSans-Bold.ttf', $fontsPath . 'DroidSans-Bold.ttf');
+
+
+
+require_once 'upgrade.php';
diff --git a/src/Upgrades/Upgrade1.sql b/src/Upgrades/Upgrade1.sql
new file mode 100644
index 00000000..8d167f6a
--- /dev/null
+++ b/src/Upgrades/Upgrade1.sql
@@ -0,0 +1,84 @@
+CREATE TABLE user
+(
+	id INTEGER PRIMARY KEY AUTOINCREMENT,
+	name TEXT,
+	pass_salt TEXT,
+	pass_hash TEXT,
+	staff_confirmed INTEGER,
+	email_unconfirmed TEXT,
+	email_confirmed TEXT,
+	email_token TEXT,
+	join_date INTEGER,
+	access_rank INTEGER,
+	settings TEXT
+);
+
+CREATE TABLE tag
+(
+	id INTEGER PRIMARY KEY AUTOINCREMENT,
+	name TEXT
+);
+
+CREATE TABLE post_tag
+(
+	id INTEGER PRIMARY KEY AUTOINCREMENT,
+	tag_id INTEGER,
+	post_id INTEGER,
+	FOREIGN KEY(tag_id) REFERENCES tag(id) ON DELETE CASCADE ON UPDATE SET NULL,
+	FOREIGN KEY(post_id) REFERENCES post(id) ON DELETE CASCADE ON UPDATE SET NULL
+);
+CREATE INDEX idx_fk_post_tag_post_id ON post_tag(post_id);
+CREATE INDEX idx_fk_post_tag_tag_id ON post_tag(tag_id);
+CREATE UNIQUE INDEX idx_uq_post_tag_tag_id_post_id ON post_tag(tag_id, post_id);
+
+CREATE TABLE favoritee
+(
+	id INTEGER PRIMARY KEY AUTOINCREMENT,
+	post_id INTEGER,
+	user_id INTEGER,
+	FOREIGN KEY(user_id) REFERENCES user(id) ON DELETE CASCADE ON UPDATE SET NULL,
+	FOREIGN KEY(post_id) REFERENCES post(id) ON DELETE CASCADE ON UPDATE SET NULL
+);
+CREATE INDEX idx_fk_favoritee_post_id ON favoritee(post_id);
+CREATE INDEX idx_fk_favoritee_user_id ON favoritee(user_id);
+CREATE UNIQUE INDEX idx_uq_favoritee_post_id_user_id ON favoritee(post_id, user_id);
+
+CREATE TABLE comment
+(
+	id INTEGER PRIMARY KEY AUTOINCREMENT,
+	post_id INTEGER,
+	commenter_id INTEGER,
+	comment_date INTEGER,
+	text TEXT,
+	FOREIGN KEY(post_id) REFERENCES post(id) ON DELETE CASCADE ON UPDATE SET NULL,
+	FOREIGN KEY(commenter_id) REFERENCES user(id) ON DELETE SET NULL ON UPDATE SET NULL
+);
+CREATE INDEX idx_fk_comment_commenter_id ON comment(commenter_id);
+CREATE INDEX idx_fk_comment_post_id ON comment(post_id);
+
+CREATE TABLE post
+(
+	id INTEGER PRIMARY KEY AUTOINCREMENT,
+	type INTEGER,
+	name TEXT,
+	orig_name TEXT,
+	file_hash TEXT,
+	file_size INTEGER,
+	mime_type TEXT,
+	safety INTEGER,
+	hidden INTEGER,
+	upload_date INTEGER,
+	image_width INTEGER,
+	image_height INTEGER,
+	uploader_id INTEGER,
+	source TEXT,
+	FOREIGN KEY(uploader_id) REFERENCES user(id) ON DELETE SET NULL ON UPDATE SET NULL
+);
+CREATE INDEX idx_fk_post_uploader_id ON post(uploader_id);
+
+CREATE TABLE property
+(
+	id INTEGER PRIMARY KEY AUTOINCREMENT,
+	prop_id INTEGER,
+	value TEXT
+);
diff --git a/src/core.php b/src/core.php
index 476872a8..30511856 100644
--- a/src/core.php
+++ b/src/core.php
@@ -43,6 +43,7 @@ function configFactory()
 
 $config = configFactory();
 R::setup('sqlite:' . $config->main->dbPath);
+R::freeze(true);
 R::dependencies(['tag' => ['post'], 'favoritee' => ['post', 'user'], 'comment' => ['post', 'user']]);
 
 //wire models
diff --git a/upgrade.php b/upgrade.php
new file mode 100644
index 00000000..93f89e17
--- /dev/null
+++ b/upgrade.php
@@ -0,0 +1,31 @@
+<?php
+require_once 'src/core.php';
+$config = configFactory();
+
+$dbVersion = Model_Property::get('db-version');
+printf('DB version = %d' . PHP_EOL, $dbVersion);
+
+$upgrades = glob('src/Upgrades/*.sql');
+natcasesort($upgrades);
+
+foreach ($upgrades as $upgradePath)
+{
+	preg_match('/(\d+)\.sql/', $upgradePath, $matches);
+	$upgradeVersion = intval($matches[1]);
+
+	if ($upgradeVersion > $dbVersion)
+	{
+		printf('Executing %s...' . PHP_EOL, $upgradePath);
+		$upgradeSql = file_get_contents($upgradePath);
+		$queries = preg_split('/;\s*[\r\n]+/s', $upgradeSql);
+		$queries = array_map('trim', $queries);
+		foreach ($queries as $query)
+		{
+			echo $query . PHP_EOL;
+			R::exec($query);
+			echo PHP_EOL;
+		}
+	}
+
+	Model_Property::set('db-version', $upgradeVersion);
+}