While attending React Conf 2016, Draft.js made it's debut as the Facebook solution to complex textareas. I had already been eager to make my first open-source package, so the thought of a plugin for Draft.js seemed like a great opportunity.
Draft.JS Gutter allows you to quickly add line numbers (or letters) to your textareas. This project didn't really take off, but it was a huge learning experience. I learned the ins and outs of publishing an open-source package.