diff --git a/src/codegen.inc.php b/src/codegen.inc.php
index 9890345..7dbd1c7 100644
--- a/src/codegen.inc.php
+++ b/src/codegen.inc.php
@@ -4,6 +4,22 @@ namespace metagen_go;
 use Exception;
 use Twig\{TwigTest, TwigFilter, TwigFunction};
 
+function codegen(?string $cache_dir, \mtgMetaInfo $meta, array $options = []) : string
+{
+  $twig = get_twig();
+
+  if(!empty($cache_dir))
+    $twig->setCache($cache_dir);
+
+  $twig->addGlobal('meta', $meta);
+
+  $options['meta'] = $meta;
+  if(isset($options['package']))
+    $options['package'] = 'autogen';
+
+  return $twig->render('codegen_bundle.twig', $options);
+}
+
 function get_twig(array $inc_path = []): \Twig\Environment
 {
   array_unshift($inc_path, __DIR__ . "/../tpl/");
@@ -501,4 +517,4 @@ function table_json_fields(\mtgMetaStruct $struct): array
 function json_field_name(\mtgMetaStruct $struct): string
 {
   return $struct->getName() . 'JsonValues';
-}
\ No newline at end of file
+}