Shopify is one of the largest Rails apps in the world and yet remains to be massively scalable and reliable. The platform is able to manage large spikes in traffic that accompany events such as new product releases, holiday shopping seasons and flash sales, and has been benchmarked to process over 25,000 requests per second, all while powering more than 243,000 businesses. Even at such a large scale, all our developers still get to push to master and deploy Shopify in 3 minutes. Let's break down everything that can happen when deploying Shopify or any really big Rails app.