The Baby Steps Push Challenge/Game

It's time we meet again! For this session (in english, you would have guessed), we'll have a special guest with us to facilitate an awesome dojo. @codecop will help us improve to code/refactor with baby steps.

This dojo will focus on working in small increments esp. in Refactoring and Integration. Please prepare an IDE of your choice. The following languages are supported: C99, Clojure, Crystal, C#, Go, Java, JavaScript, ES6, Kotlin, PHP, Python, Ruby, Rust, Scala and TypeScript.

Note:
Please also send us you github handle, it's mandatory for this kata (and it will be fun).