Eucalyptus Systems, the startup behind the open source cloud computing software, has identified its first two customers: NASA and Eli Lilly. That's an impressive start for a company that's barely three months old.Eucalyptus Systems was officially launched in April, when the company revealed it had secured $5.5 million in Series A funding from Benchmark Capital and BV Capital. The startup is a spin-off of the University of California at Santa Barbara, where its founders developed the software as part of a research project that involved linking National Science Foundation supercomputers with public cloud services for scientific workloads. Eucalyptus is the open source platform resulting from that work, and Eucalyptus Systems is the software company behind the platform.

When I spoke to Eucalyptus Systems CTO Rich Wolski a few days ago, he told me the company had five customers and about 10 others in the queue. The early adopters include Eli Lilly, which has been blazing a trail in the cloud market, and NASA's Jet Propulsion Lab. (For more on what they're doing in the cloud, see "Eli Lilly On What's Next In Cloud Computing" and "NASA Launches 'Nebula' Compute Cloud.") That's just Eucalyptus Systems' paying customers. Hundreds of other companies have downloaded the free, open source Eucalyptus software.

Eucalyptus supports the Amazon Web Services API, so virtualized images can move back and forth between Eucalyptus clouds and Amazon's Elastic Compute Cloud and Simple Storage Service. As it happens, Eli Lilly is an AWS user, and NASA has designed its Nebula cloud to be AWS compatible. We suspected that interoperability between private clouds and AWS would be important; we now know that to be the case.

Eucalyptus Systems has dabbled with other APIs, but the demand isn't there yet. "Amazon owns the market share," Wolski says.

Eucalyptus Systems is still a newbie to the commercial open source market. In the months ahead, the company plans to introduce tiered pricing for its support services and develop software add-ons that make the platform better suited for enterprise deployment. It also intends to host operating system images other than Linux, including Windows and Solaris.