Recently I rediscovered a coding exercise app. Exercism. It’s a CLI tool that downloads one exercise at a time. It has exercise for over 30 programming languages. Each problem typically contains a README file and a test file like below README.md exercise.spec.js For ES6 or ECMAScript will have the language specific files package.json gulpfile.js Once you’ve completed the coding exercise, you can run the test and makes sure all the tests passed.