Rails core team decided to not include Rails.queue in the 4.0 release. @jeremy has a nice writeup for the reasons:
- Resque’s interface is currently easier to use than Rails.queue’s
- Marshalling has some issues
- Rails.queue is abstracting at the wrong level (equivalent to imaginary Rails.database)
- Not efficient when working with Russian doll caching
- There might be a better way to avoid marshalling and Job classes alltogether by processing certain jobs after the response has been sent to client. However this requires work on the Rack integration.