User problem:
-----------------------------------
--

User need:
-----------------------------------
As the source base gets older, the amount of code
that is not more called from anywhere grows. The
user would benefit from being notified about such
code, to maintain the quality of the codebase
high. Explicit tool that the user could invoke
would be also helpful, but the added value of
background detection is that the user does not
have to think about doing the cleanup once in a
while (many developers never do this)

Product requirement:
-----------------------------------
Background detection of unused code