In this chapter, we learned the basics of the Magento shipping method implementation. Based on that, we built our own simple shipping method that further implemented several business rules. Our extension was built with a presumption of using the default Magento installation with USD ($) currency only and no tax configured. When building an extension for distributing, you will need to dig a bit deeper into it, covering the currency and tax calculations. Since the focus of this chapter was on overall introduction and a basic shipping example, we leave it up to you to handle more complex shipping methods.
In Chapter 5, Building the Extension - Payment, we will familiarize ourselves with payment methods and build a payment extension.