Google App Engine vs tsuru: What are the differences?

What is Google App Engine? Build web applications on the same scalable systems that power Google applications. Google has a reputation for highly reliable, high performance infrastructure. With App Engine you can take advantage of the 10 years of knowledge Google has in running massively scalable, performance driven systems. App Engine applications are easy to build, easy to maintain, and easy to scale as your traffic and data storage needs grow.

What is tsuru? Extensible and open source Platform as a Service software. tsuru is an open source polyglot cloud application platform (PaaS). With tsuru, you don’t need to think about servers at all. You can write apps in the programming language of your choice, back it with add-on resources such as SQL and NoSQL databases, memcached, redis, and many others. You manage your app using the tsuru command-line tool and you deploy code using the Git revision control system, all running on the tsuru infrastructure.

Google App Engine and tsuru can be primarily classified as "Platform as a Service" tools.

Some of the features offered by Google App Engine are:

• Zero to sixty: Scale your app automatically without worrying about managing machines.
• Supercharged APIs: Supercharge your app with services such as Task Queue, XMPP, and Cloud SQL, all powered by the same infrastructure that powers the Google services you use every day.
• You're in control: Manage your application with a simple, web-based dashboard allowing you to customize your app's performance.

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

• Fast and secure. The entire process is really simple with no special tools needed, just a simple git push.
• Scaling in Tsuru is completely painless. Just add a unit and Tsuru will take care of everything else.
• Tsuru is built to be extensible. Through services you can provide anything your application needs.

"Easy to deploy" is the primary reason why developers consider Google App Engine over the competitors, whereas "Very receptive to contributions" was stated as the key factor in picking tsuru.

tsuru is an open source tool with 3.14K GitHub stars and 421 GitHub forks. Here's a link to tsuru's open source repository on GitHub.