The rest of the economy is recovering slowly, but a young firm that helps big names on the Internet expand their businesses is set to lift off. Five-year-old Appirio, partner to Facebook, Twitter, and Salesforce.com, announced Thursday that it's received $60 million in funding to expand both its development platform and cloud software suite.

The investment was lead by General Atlantic, with participation by Sequoia Capital and GGV Capital. No other startup in the Silicon Valley cloud market is known to have garnered as large a take in a single round of funding.

Appirio will use the money to build out its current San Mateo, Calif., 500-person staff, three-quarters of whom are programmers or "cloud engineers," and to do mergers and acquisitions, according to Narinder Singh, co-founder and chief strategy officer.

Appirio has concentrated on building a set of re-useable assets for connecting, integrating, and scaling up applications on public infrastructure-as-a-service, such as Amazon's EC2. Appirio built a link between Salesforce.com's CRM data and Google's Gmail. Through it, contact information in Salesforce.com can be moved into a Gmail message. Appirio staffers have worked with Salesforce.com on internal initiatives since it was founded in 2006.

[ Want to learn more about one of the specific integrations that Appirio has done? See Appirio Builds Salesforce To Gmail Link. ]

It's only worked with Twitter for six months. But in the funding announcement, Twitter president of global revenue Adam Bain said, "Appirio has become a trusted adviser and partner, helping us scale our operations and execute our solutions as quickly as we can think of them."

Even more important is the intellectual capital that Appirio has demonstrated that it commands. Appirio founded CloudSpokes, a developer network with a focus on cloud projects and applications. CloudSpokes doesn't provide language tools or programming aids, as much as a forum where cloud developers get together to talk over issues and compete to meet challenges, issued in the form of contests.

Daniel Llewellyn, better known as Kenji776 on CloudSpokes, is a 23-year-old programmer who was attracted to the environment a year ago. The Minneapolis resident considered himself a fair JavaScript, Ajax, and Cold Fusion developer but doubted he could compete with participants he found on CloudSpokes.

But he won the first challenge he took up, which consisted of outsmarting the restrictions built into the Salesforce.com User Profile page so that a company using it could customize it with a button pulling in additional, Web-referenced content.

"That first challenge couldn't have been better suited to my personality," he recalls. It required someone knowledgeable in networking, who liked hacking through restrictions to come up with a useful mechanism. He did and won $200, a pittance for the company seeking the hack to have to pay out, but an enticing supplement to Llewellyn's day-job salary.