Using a version control system, like Git, is nice. However, when building an extension from scratch and loading it via Composer, it adds a lot of pain in the butt steps. You have to commit your changes, update composer to pull them over, then notice there is an error, fix, commit, update. repeat.. I don't want all my baby steps under Git. Sure, I could edit my commit history, but c'mon. Just let me code! I will put it under version control once I get a baseline created. This guide will show you how to setup your composer.json to load a local directory (everything inside, live). You make a change, save the file, refresh the page, boom.
After installing Yii basic application on our systems, most of the time we want to have multiple environment such as local, dev and live setup. Most of the times when we want to make changes to configuration file, we have to over-write configurations file for each environment.