At first blush, the software Netflix open sourced on Monday seems like part of an elaborate joke. The company has made its storied Chaos Monkey—a software service that deliberately attacks and randomly disables resources the company runs in the Amazon Web Services cloud—available on GitHub under an Apache license. It did this just in case, you know, anyone else wants to install some software designed explicitly to cause service outages.
But read more about Netflix's decision and the company's rationale becomes clear: Perpetually grappling with the Chaos Monkey is the best way to ensure that Netflix services can withstand widespread outages. By building failure into its architecture, Netflix guarantees that its engineers are constantly aware of issues that could affect the quality of its services—and are repairing them before customers even notice.
"We have found that the best defense against major unexpected failures is to fail often," employees Cory Bennett and Ariel Tseitlin wrote on the company's blog. "Do you think your applications can handle a troop of mischievous monkeys loose in your infrastructure? Now you can find out."
It's been a week of open source news from Netflix, which also recently announced a new effort to crowdsource closed captioning for its content. According to Gigaom, the company is establishing a subtitling community on Amara so it can test the viability of crowdsourcing this important resource. Netflix has received criticism for failing to make streaming content accessible to deaf and hearing-inpaired viewers, so the results of this experiment in producing captions the open source way could be critical.
All this comes only weeks after Netflix reiterated its commitment to open source technologies.
"We have benefited from many other people contributing to open source," wrote employee Ruslan Meshenberg, "so we are paying back in kind."