Developers may be interested in using PostgreSQL as a Celery broker, rather than Redis. This could eliminate the need for a separate server and reduce costs. A GitHub issue highlighted PostgreSQL's potential as a task queue broker, leading to the discovery of BQ, an alternative task queue that leverages PostgreSQL's NOTIFY function. BQ offers a unique pub-sub model, which can improve efficiency by reducing constant polling. However, developers should consider factors such as resource consumption and the noisy neighbor problem when evaluating this option.

Source: https://dev.to/k4ml/postgresql-as-a-celery-broker-d8d