This post will describe how to compile a small application written in Kotlin using Bazel, tests, as well as how to use static analyzers. Phosphorus Phosphorus is the application that this post will cover. It’s a small utility that I wrote to check if an image matches a reference. If it doesn’t, Phosphorus generates an image highlighting the differences. The goal is to be able to check that something generates an image in a given way, and doesn’t change - at least if it’s not expected.