Yes, it's certainly possible to let have a dependency on the storage method in your design. I won't say this is bad, but it's not how I would do it. I would do the design of the backbone first, and have it not tainted with storage method. The problem with that is that it's harder to switch to a different storage method (and I don't mean switching from YAML to Data::Dumper, but switching from flat files to DB files, or somekind of database), because the storage method is too much wired in. If the storage method is an 'add-on', it's easier to replace.

As for this particular problem, several methods have already been mentioned. Writing down a comparison between all the methods would take too much of my time - the OP can do some work as well, and download the various modules and read the documentation.

But you are free to write an article, comparing the various storage modules, and how they are more or less useful in the project the OP is undertaking.... ;-)

Abigail