Vitruvius is a framework and set of tools to help the code architect analyze a code base.

Application services, on the other hand, are a great way to introduce a layered architecture. They can be used for mapping data inside the domain model to a shape required by a client application. For example, maybe you need to display tabular data in a DataGrid, but you want to maintain a granular and jagged object graph in your model.

draw.io is free online diagram software for making flowcharts, process diagrams, org charts, UML, ER and network diagrams