Netflix has moved its Eureka mid-tier load-balancing tool, formerly known as the Netflix Discovery Service, to open source.
From the Netflix announcement of the move:
Eureka is a REST based service that is primarily used in the AWS cloud for locating services for the purpose of load balancing and failover of middle-tier servers. We call this service, the Eureka Server. Eureka also comes with a java-based client component, the Eureka Client, which makes interactions with the service much easier. The client also has a built-in load balancer that does basic round-robin load balancing. At Netflix, a much more sophisticated load balancer wraps Eureka to provide weighted load balancing based on several factors like traffic, resource usage, error conditions etc to provide superior resiliency. We have previously referred to Eureka as the Netflix discovery service.