Quick fix to DefaultRegistration

src/Language/DefaultRegistrations.php

@@ -78,6 +78,7 @@ class DefaultRegistrations implements LanguageRegistration
 
     public function registerExtension(Compiler $compiler) : void
     {
+        $compiler->registerExtension(new \Picea\Extension\PhpExtension());
         $compiler->registerExtension(new \Picea\Extension\JsonExtension($this->context));
         $compiler->registerExtension(new \Picea\Extension\AssetExtension());