We are in need of a queuing system in our Ruby On Rails 4 web application
what are the differences and why would/wouldn't you pick
Sidekiq over RabbitMQ ?
It's quite different things with different usage. Sidekiq is full-featured solution for job queueing and processing, while RabbitMQ is just a message broker where you can build your own stuff upon it.
来源：https://stackoverflow.com/questions/34525941/sidekiq-vs-rabbitmq