On success, GNU Artanis returns the status code 200.
If there’s any issue prevents GNU Artanis to generate requested result successfully, then it’ll throw the relavent exception somewhere issue happened. And finally it will be caught by the server-core. In theory, the status code other than 200 will trigger a system page generating operation. By default, status pages are put in /etc/artanis/pages, but you may override it in your_app_folder/sys/pages. Each system page named with the status code, say, 404.html. So you may easily customize your preferred status page.