Software metrics can be used effectively to judge the maintainability and architectural quality of a code base. Even more importantly they can be used as “canaries in a coal mine” to warn early about dangerous accumulations of architectural and technical debt. Therefore using the right metrics can improve project governance and outcomes.

Software architecture can be defined as the internal structure of a software system. As such it influences many critical aspects of software systems like maintainability, comprehensibility, changeability and security. One would think that given the importance of a good architecture most systems would be well structured and not suffer from large amounts of structural or architectural erosion. Just the opposite is true. Most non-trivial systems with more than 100,000 lines of code are in bad shape and require enormous efforts to keep them alive. Developers spend most of their time with figuring out complex interdependencies in the code base.