In this, the final episode on Architecture, we begin by discussing the structure of business rules and business data. Then we talk about how architectures should scream those business rules to programmers. Next we walk though a prototype four layer architecture that I like to call The Clean Architecture. Lastly we spend some time talking about all the low level things that don't neatly fit into any architecture. Things like main, configuration, tests, and low level drivers and utilities. And finally, we talk about how to get off the planet. Have fun, everybody!