Nerval's Lobster writes "Netflix has released Hystrix, a library designed for managing interactions between distributed systems, complete with 'fallback' options for when those systems inevitably fail. The code for Hystrix—which Netflix tested on its own systems—can be downloaded at Github, with documentation available here, in addition to a getting-started guide and operations examples, among others. Hystrix evolved out of Netflix's need to manage an increasing rate of calls to its APIs, and resulted in (according to the company) a 'dramatic improvement in uptime and resilience has been achieved through its use.' The Netflix API receives more than 1 billion incoming calls per day, which translates into several billion outgoing calls (averaging a ratio of 1:6) to dozens of underlying systems, with peaks of over 100,000 dependency requests per second. That's according to Netflix engineer Ben Christensen, who described the incredible loads on the company's infrastructure in a February blog posting. The vast majority of those calls serve the discovery user interfaces (UIs) of the more than 800 different devices supported by Netflix."