What is "scalr"

Scalr is an open source Cloud Management Platform for managing multi-cloud infrastructure. The project was started and open sourced in April 2008 to provide scalable infrastructure for MediaPlug (a media sharing service) and is now maintained on GitHub. Scalr provides, according to one reviewer, "90% of the features, at 10% of the price" of main competitor RightScale.

The code is made freely available under the Apache License (version 2.0) and Scalr has received favorable reviews from sites including TechCrunch, HighScalability, the official AWS blog, and CNet.

Scalr is also available as a monthly subscription service since mid-2009.