Writing command-line interfaces, whether it's to string together a few oft-forgotten terminal commands or batch automate repetitive tasks, are one of those things most developers eventually do, but often only do just "good enough." Let's shift the focus from clean and beautiful application code to CLI's! What makes a reliable, user-friendly CLI? When should we use flags vs config files vs interactive wizards? Speaking of wizards, how do we put pretty spinners and menus in a CLI? How do we test it? Let's spend some time obsessing over these oft-neglected scripts!