The goal of this repo is to keep a few tasks that a developer should be able to perform at each level of his career (according to my experience). It was created to help those starting on IT, but these tasks may be helpful if you are a frontend engineer who wants to know more about the backend side or a backend engineer who wants to know how their services can be presented to real users. It also could be helpful (and this is how I have been using this kind of task) if you are starting a new programming language, as you could start doing an entry-level task and getting deeper as you want.
https://github.com/pedrovsn/data-structures
Repo which contains a series of data structures and algorithms frequently asked on job interviews.