3. Challenge Build Your Own Array In JsThis is a challenge that will allow you to practice your logical, analytical and problem-solving skills. Additionally, by the end of it you’ll have much better command of arrays in javascript.
5. Spec2.crEnhanced `spec` testing library for [Crystal](http://crystal-lang.org/).
6. Mysql adapter.crMysql adapter for [active_record.cr](https://github.com/waterlink/active_record.cr). Uses [crystal-mysql library](https://github.com/waterlink/crystal-mysql)