By having learners' clients query for a specific S3 file, we could toggle BRB by modifying that file. Instead, we decided on AWS S3, a simple, high-availability storage service with a key feature: access logs. Originally we planned a microservice, but that introduced many additional dependencies. BRB should have few dependencies, be easy to use and maintain, and be usable even when the site is down. When deciding how to move forward with BRB, we sought solutions that were simple, yet robust. These issues can be compounded due to ongoing higher-than-normal traffic, which might happen because learners are concerned about their streaks, and continue to retry lessons.īig Red Button (BRB for short) is an internal project which allows us to pause requests, inform learners of the pause, gradually bring requests online as problems are resolved, and repair streaks that were interrupted.

Site issues can be caused by internal or external software changes or hardware failure, internet outages, or even unexpected learner behavior (drastically more traffic due to a Duo meme, for example). We've put a great deal of effort into improving and hardening our underlying infrastructure, but… things happen. How do we protect streaks, inform learners that their streaks are safe, and bring systems online faster? That's where Big Red Button comes in. During a site issue, learners are concerned about maintaining their streaks, so it's important that we protect their streaks (those are hard work to earn!) while also moving quickly to resolve the issue. And we know that streaks are an important motivational tool for learners. At Duolingo, we always put learners first.

Red button meme ignore