This example shows how to serve NiceGUI on a subpath behind a reverse proxy. Here we use Nginx. For a Traeffic example have a look at https://github.com/zauberzeug/nicegui/blob/main/docker-compose.yml.
Just run
docker compose up
Then you can access http://localhost/nicegui/. Note the trailing "/" in the URL. It is important. We welcome suggestions on how to make it optional.