I’d love to see one for Elixir built around the Postgres pgmq and pg_crom extensions similar to what pgflow is doing: https://www.pgflow.dev/
The worker is stateless and "dumb" by design (currently it runs on serverless functions) - it just calls SQL functions: "poll_for_tasks" to get some tasks from the queue and then either "complete_task" or "fail_task" after executing user code - that's it, nothing more, so it should be relatively easy to adopt it to other runtimes.
I have written a small architecture primer on pgflow if anyone is interested in its simple but flexible design https://www.pgflow.dev/concepts/how-pgflow-works/