The Ephemeral Container Service (ECS) was born out of the Cloudfeaster project. Docker makes it easy to package short lived (aka ephemral) tasks in a docker image and run those tasks using the docker client. The Docker Remote API makes it possible to do this using requests to a RESTful API. Cloudfeaster used these building blocks to package spiders in docker images and run those spiders in docker containers on a cluster of docker hosts. ECS is a generalization of these basic building blocks.