[latchkey]

The end user doesn't need to implement the queue or the worker. They just need to implement the http api for receiving POST messages. The queue "server" is effectively just a http client that reads messages from the database and sends them off.

[ryeguy]

That makes sense as a general pattern, but probably less so in the context of rails which is typically a self contained monolith. It would be adding another hop, more indirection, and more complexity. It would introduce new problems like the need to segment your "real" api from your worker api for the purpose of load isolation.

[latchkey]

If it is a self contained monolith, that's perfect for this. You have a long running process, which scans a database for new work and then posts to localhost.