Deis doubles down on Docker, for app deployment and its own delivery

The transformation of the Heroku-inspired application platform into a series of Docker images is the latest example of Docker's expanding influence as a platform

In the space of barely a year, Docker's gone from a novelty to a near-cornerstone of the Linux application world. And it's not hard to see why: it provides a convenient way to take an application, package it, deploy it in isolation on a target machine, and work in conjunction with any of a number of commonly-used infrastructure automation tools.

The latest example of Docker as a cornerstone software solution involved Deis. Inspired by Heroku, Deis is an open-source (Apache-licensed) PaaS designed to deploy and scale Docker containers, Heroku buildpacks, and Chef nodes for application hosting. Multiple languages are supported out of the box by Deis, from Java, Python, and Node.js, to Clojure, Dart, and Go, but in theory, Deis can deploy anything packaged up with Docker or Heroku.

The latest release of Deis, 0.5.1, is where things get interesting: now, Deis itself is being delivered as a series of Docker images. The idea here is to have each component of Deis delivered as a separate image, all of which then interlock seamlessly on deployment. Each individual piece can be swapped out or upgraded separately if needed, making it easier to deploy and manage Deis.

Another Docker-centric addition to the new version of Deis allows any application to be built and deployed based on a Dockerfile for that app. Future additions to Deis appear to be all the more Docker-influenced as well -- e.g., the ability to promote existing Docker images as builds directly from a Docker Registry.

Docker's role as an application delivery solution has mushroomed in recent months. Most recently, Red Hat started a certification program to verify the delivery of Dockerized apps on RHEL. Containerization of apps is starting to look like a good alternative to full-blown virtualization in many cases. It's even landed on Black Duck's list of the best new open source projects of 2013.

What comes next, it seems, is using Docker as both the underlying solution for a given app-delivery problem and the infrastructure to deliver that solution. Deis may well be the first of many such approaches to that concept, in much the same way Chef, Puppet, Salt, and Ansible (the latter being tightly integrated with Docker as well) were all their own solutions to the problems of system configuration and orchestration.