My own vision for Melody is a code base that's very focused on publishing and content management, with all the infrastructure outsourced to CPAN modules that are well-written, well-documented, and well-tested. The collaboration between Melody and CPAN would be a two-way code flow. While there are more CPAN modules that Melody could make use of, there are number of pieces of Melody which should be packaged as independent modules on their own and released to CPAN. One example is the great "dirification" that already exists in Movable Type. This is the functionality that turns any given string of words into a reasonable representation in URLs. It seems like an easy problem on the surface, but Movable Type has a sophisticated solution that takes into account what it means to do this well across many different languages. I also couldn't find any existing CPAN module which already takes on this problem space, so I started to extract this out of Movable Type myself and published a draft of String::Dirify. For that initial release, I ripped out all the fancy multi-language support, and there is still more significant work to be done to untangle this layer from from Movable Type. ( If you want to pick up that project and work on it, there's also some discussion of testing String::Dirify).
While Movable Type already had an open source release, I expect Melody to have a more adventerous evolution, and I look forward to it becoming a shining star in the Perl community, not just for the exterior functionality, but also because internals have an opportunity to become an example of best practices.