Quoting:
"[A] new metric to track maintainability.
A good metric to measure software maintainability is the holy grail of software metrics. What we would like to achieve with such a metric is that its values more or less conform with the developer’s own judgment of the maintainability of their software system. If that would succeed we could track that metric in our nightly builds and use it as the canary in the coal mine. If values deteriorate it is time for refactoring. We could also use it to compare the health of all the software systems within an organization. And it could help to make decisions about whether it is cheaper to rewrite a piece of software from scratch instead of trying to refactor it.
A good starting point for achieving our goals is to look at metrics for coupling and cyclic dependencies. High coupling will definitely affect maintainability in a negative way. The same is true for big cyclic group of packages/namespaces or classes. Growing cyclic coupling is a good indicator for structural erosion. (...)"
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"Try it yourself
Now you might wonder what this metric would say about the software you are working on. You can use our free tool Sonargraph-Explorer to compute the metric for your system written in Java, C# or Python.
is currently only considered for Java and C#. For systems written in C or C++ you would need our commercial tool Sonargraph-Architect."