The last month of each year is always a special one. As some might be familiar with the concept of an advent calendar, there is a special competition starting each year on December 1st: Advent of Code. Counting down each day until Christmas, you are sent off on an adventure that requires you to solve a series of puzzles. Each day a new challenge is unlocked, and each challenge consists of two parts. Solving a challenge successfully yields you gold stars, and obtaining the total of 50 gold stars usually means you have saved Christmas.

TIL: Go has a built-in "race detector" which helps you catch race conditions in production code. The Go toolchain really is awesome!

After successfully running a single Redis GCE instance to manage our inter-service communication for a couple of years, we finally started to run into scaling issues. To solve these, we started working out a way to reliably run a set of Redis instances as a cluster in our Kubernetes cluster.