Medium Describes “Rex” – a Go-Based Recommendation Service

In a recent blog post, Medium describes how it built a recommendation service named “Rex.” The original recommendation service was part of the Node.js monolith, and it could only rank 150 stories. However, Medium wanted this service to rank hundreds of thousands of stories per user in under a second. So, they decided to build an entirely new, separate service using Go. (Read more on InfoQ)