Because architectures are intangible, they often become lost or eroded over a system's lifetime. That is why we need techniques to recover or extract an architecture from a legacy system. This chapter provided an overview of a standard architecture reconstruction and showed an extended example of its application.
The mapping between architectures and source-code-level system artifacts is complex, and this makes architecture reconstruction a complex process that works best when it engages available human knowledge about the system under consideration. Tools are invaluable, especially when arrayed in a lightweight workbench ensemble, but human knowledge and insight are even more invaluable to guide the reconstruction process.