Git.io is a URL shortening service designed for GitHub URLs, allowing users to create shortened links using curl commands, and even specify custom codes for vanity URLs. Developed as an experiment by Risk Olson and @atmos, Git.io leverages Riak databases and is deployed on Rackspace Cloud, offering a platform to explore and refine technology implementations. The service is part of a broader initiative to experiment with new technologies like the Riak 1.0 upgrade, which involved a rolling upgrade across their cluster, and to enhance deployment management through tools like Hubot and puppet scripts. Users can also create their own URL shorteners using Guillotine, a Ruby-based hobby kit that supports storing links in Riak or relational databases.