Deis vs Flynn: What are the differences?

Developers describe Deis as "Open Source PaaS that builds upon Docker and CoreOS to provide a lightweight PaaS with a Heroku-inspired workflow". Deis can deploy any application or service that can run inside a Docker container. In order to be scaled horizontally, applications must follow Heroku's 12-factor methodology and store state in external backing services. On the other hand, Flynn is detailed as "Next generation open source platform as a service". Flynn lets you deploy apps with git push and containers. Developers can deploy any app to any cluster in seconds.

Deis and Flynn belong to "Platform as a Service" category of the tech stack.

Some of the features offered by Deis are:

• Deis can deploy any language or framework using a Dockerfile
• If you don't have a Dockerfile, Deis includes Heroku buildpacks for Ruby, Python, Node.js, Java, Clojure, Scala, Play, PHP, Perl, Dart and Go.
• Deis can be deployed on any system that supports CoreOS including your workstation, as well as most public clouds, private clouds and bare metal.

On the other hand, Flynn provides the following key features:

• Flynn goes beyond 12 factor apps. Run any Linux process written in any language or framework, even stateful apps on your own servers or any public cloud.
• Scaling or adding a new cluster is simple: just add more nodes. Everything is containerized, Flynn takes care of distributing work across the cluster.
• Flynn is 100% free and open source. Flynn works great out of the box, and since Flynn is modular and API-driven it's easy to modify and swap components to suit your needs.

"12-factor methodology" is the primary reason why developers consider Deis over the competitors, whereas "Free" was stated as the key factor in picking Flynn.

Deis and Flynn are both open source tools. It seems that Flynn with 7.24K GitHub stars and 534 forks on GitHub has more adoption than Deis with 6.12K GitHub stars and 863 GitHub forks.