Maven has the lame dependency conflict resolving rule of 'the closer the better': if 2 versions exists for a library, only the one closest to the trunk of the transitive dependency tree will be kept, the others will be dropped from classpath. This has caused pervasive instability in all projects build by maven.
I would like to address this problem from 2 sides:
use conflict detection analyzer like JHades to scan everything in the classpath, and report version conflict from within the classloader
use a fancy classloader to situationally customise the classpath, such that the correct version will be used at the right moment. This is also the method adopted by OSGi
To achieve either of them I need to override maven such that it append the jars of the further versions into the classpath in various lifecycles ('test' in particular). How do I achieve this?
UPDATE: I realise maven is an old product and wasn't design with megaproject that has thousands of dependency in mind. So if you have a solution in Gradle, Pants, Buck, sbt, or any esoteric build tools, I will still accept it as a valid answer.