https://github.com/rqlite/rqlite
Pronounced “ree-qwell-lite”
http://jasonwilder.com/blog/2014/02/04/service-discovery-in-the-cloud/
Service discovery is a key component of most distributed systems and service oriented architectures.
The problem seems simple at first: How do clients determine the IP and port for a service that exist on multiple hosts?
Solutions described in the blog post:
http://techblog.netflix.com/2014/11/introducing-dynomite.html
I found this write-up about the technology to be pretty interesting.
A great blog post detailing how https://bitly.com/ scales their URL shortening service.