OpenStack Mitaka is the 13th release from the open-source cloud effort, which Rackspace and NASA began in June 2010. The OpenStack community has grown significantly, and the technology is now used at some of the largest organizations, including Walmart, eBay, PayPal, AT&T, Comcast, IBM, Cisco, Dell, Intel and Hewlett Packard Enterprise.
Mitaka follows Liberty, which debuted in October 2015 and was the first release to follow the so-called Big Tent model. OpenStack is made up of a collection of projects that enable different capabilities. With the Big Tent, the number of projects considered to be part of OpenStack grew significantly.