This is the first in a series of posts about adding containers to our server farm to make it easier to scale, manage, and keep pace with our business. The key ingredients are: Docker: container technology for making applications portable and predictable CoreOS: provides a minimal operating system, systemd for orchestration, and Docker to run containers Shopify is a large Ruby on Rails application that has undergone massive scaling in recent years. Our production servers are able to scale to over 8,000 requests per second by spreading the load across 1700 cores and 6 TB RAM.