How to ‘wp package install’ in wpcli docker container

Using docker-compose with a config such as

# ...
  wpcli:
    depends_on:
      - wordpress
    image: wordpress:cli
    user: 1000:1000
    command: tail -f /dev/null
    volumes:
      - ./wordpress:/var/www/html
    environment:
        - WORDPRESS_DB_HOST=mariadb:3306
        - WORDPRESS_DB_USER=wordpress
        - WORDPRESS_DB_NAME=wordpress
        - WORDPRESS_DB_PASSWORD=${MARIADB_PASSWORD}

You need to install the package in the container as root to avoid

Error: Composer directory '/.wp-cli/packages' for packages couldn't be created: mkdir(): Permission denied

Use the following command to install a package

docker-compose exec -u root wpcli wp package install wp-cli/profile-command:@stable --allow-root