SaaS-delivered API management tool Mashery has raised $10 million to further what it calls the “post-website era,” led by OpenView Venture Partners and other with participation from existing investors including Cisco, Formative Ventures, First Round Capital and .406 Ventures.

Mashery’s vision hinges on the idea that APIs are the future of services. With its API management platform, Mashery aims to help data service providers, e-retailers, and essentially anybody else launch and manage API access to software (including setting up tiered access and allowing for the bundling of associated APIs), in turn making it easy for developers to build an ecosystem around your product.

And the response has been significant: With this funding announcement, Mashery is announcing a 272 percent increase in traffic, year over year, with a 30% rise in developers over the same period to a total of 160,000. 50,000 total applications are built using Mashery for API management, a 75% more than last year.

In a statement, Mashery says that it’s going to use the money to expand its global operations, focusing on sales and marketing efforts.

In Mashery’s case, the name really says it all. There’s a really interesting conversation happening in the cloud right now about the role of APIs – in the cloud services marketplace, the API isn’t just a component, it’s often the product itself. Recently, Eucalyptus CEO Marten Mickos referred to the API market as a “symphony,” with customers able to piece together a complete, customized cloud by picking and choosing their APIs and very little else. That’s why an open API economy is absolutely vital to the future of the cloud.

And that goes double when you consider the impact of mobile, as APIs are the lynchpin of enterprise app usage in particular and the App Store economy in general.

“The advent of the iPhone inside offices was a great problem for us. The iPad was a better one. Mobile app usage volume within most companies has made it so that more apps are being written, and companies need to access their own data and assets, as well as give them to partners. Companies are now using APIs as their product. There’s more of a sense that people are waking up to APIs quicker and more often,” writes Mashery co-founder Oren Michels in a blog highlighting his company’s growth.

And while Mashery’s business isn’t necessarily limited to the cloud marketplace, it definitely does plenty of business there. If it’s seeing this kind of success, with $34.8 million raised overall in its six years of life, then it definitely says that yes, there’s an API economy, and enterprise developers are investing heavily therein.