Slow requests to third party payment gateways or sudden spikes in image uploads make background jobs crucial to scaling applications. However, they require us to think differently about failure scenarios: we give up consistency guarantees, and we can’t be certain if or when a job will succeed. In this talk, you’ll learn how to get the started with background jobs, master the challenges they're posing, and how they are used at Shopify to scale one of the largest running Rails applications.