Daemon
A Daemon is a common workload which runs in parallel to the application to perform auxilery tasks.
Daemons faciliate many complex application topologies including the worker pattern used by Symfony Messenger.
For more information on Symfony Messenger see Daniel Phin's blog post about integrating it with Drupal.
You can configure daemons to run from either your project defaults or environment configuration files using the format below:
daemon:
chat-aggregator:
command: "sleep 300"
suspend: false