email_registration-8.x-1.1/email_registration.services.yml

services:
  email_registration.route_subscriber:
    class: Drupal\email_registration\Routing\RouteSubscriber
    tags:
      - { name: event_subscriber }
  Drupal\email_registration\UsernameGenerator: '@email_registration.username_generator'
  email_registration.username_generator:
    class: Drupal\email_registration\UsernameGenerator
    arguments: ['@uuid']