Netflix releases ‘Chaos Monkey’ code to help developers defend against outages

For over a year now, Netflix has been using a “Simian Army” of apps designed to attack its own servers as a way to ferret out bugs before they affect end users. Today, the company is releasing one of those tools to all developers. Called “Chaos Monkey,” it’s designed to help those who use “virtual machines” on services like Amazon Web Services (AWS) by randomly turning off some of those machines. AWS works by allowing a website or web app to run off of multiple (sometimes hundreds) of virtual machines, and sites using AWS can be (and usually are) configured to handle individual outages without hassle.

However, the complexities of modern-day web app development mean that there are always surprising bugs that can crop up. Although Chaos Monkey probably wouldn’t help a developer recover from a catastrophic failure like the outage that struck AWS a month ago, it could theoretically help developers harden their web apps against smaller problems. Given how many sites depend on AWS, the tool could be a boon for many popular services like Pinterest and Instagram.

Netflix has a history of releasing its own tools to the larger developer community, and Chaos Monkey is just the most recent example. As Ars Technica notes, Netflix’s Github for the project contains hints that other simian-themed tools will be released to developers in the future.