The Netflix API launched in 2008 with the same hope as many API providers: to attract developers who would build amazing applications on top of the service. Fast-forward 3 years: with more than 23 million subscribers in the United States and Canada, Netflix is the world's leading Internet subscription service and the way in which millions of people are watching movies and TV shows -- not just via DVDs shipped to their home, but increasingly online.
The Netflix API was a success, but not in the way the company anticipated. Third-party developers did build some cool applications. But where the API really succeeded was internally for Netflix itself -- piping movies and TV shows to over 200 devices, setting the stage for the company's next round of growth. The success of Netflix instant now shows in the company's recent API changes, removing DVD-related calls to focus on instant, where the company has seen such tremendous growth.
Externally, this growth isn’t apparent. What you see publicly in the Netflix developers area is only the tip of the API iceberg. At the 2011 O’Reilly Velocity Conference last week, Netflix's Adrian Cockcroft outlined how APIs are the center of its system architecture, and essential to their growth.
The APIs that Netflix uses internally have decoupled its systems, unwinding years of legacy code, making them more flexible and allowing them to move their legacy, data-center infrastructure to operate almost completely in the Amazon Cloud.
Facing unprecedented, and unpredictable growth, Netflx could only look to the Amazon Cloud to provide the scale it needed. Before it could migrate, it had to untangle the complex set of objects and dependencies that made up its data-center operations and its legacy Oracle database.
Netflix opted to go with a set of API to deliver the services it needed, something that would give its systems the flexibility and independence needed to scale the way Netflix operations needed to.
With a flexible API core and with systems running almost entirely in the cloud, Netflix plans to expand into an additional markets in the second half of 2011. And if the second market delivers as expected, it will continue to invest and expand aggressively in 2012.