A system includes a plurality of queues configured to hold tasks and state information associated with such tasks. The system further includes a plurality of listeners configured to query one of the plurality of queues for a task, receive, in response to querying one of the plurality of queues for a task, a task together with state information associated with the task, effect processing of the received task, and communicate a result of the received task to another queue of the plurality of queues, the another queue of the plurality of queues being selected based on the processing of the received task.