Classes er dead - long live interfaces

The above headline is a catchphrase used by Qi4j. While classes are nowhere near dead, even in Qi4j, the Composite Oriented Programming paradigm Qi4j presents seems really promising.

While I have only used Qi4j in my small "Hello World" kinda examples, I must say it just feels right - compositions of fragments, side-effects (a long time pet peeve of mine) and mixins IS the way of the future of programming and software design.

Now I've been thinking about why Qi4j isn't very hyped or even mentioned in main-stream programming media's, and I think the fact that you have to more or less go "all-in" scares most. I mean, you can't mix Qi4j with a normal DAO kinda project, you HAVE to use their persistence framework and Unit-Of-Work setup. I feel the Composite part should have been separated from the UoW part, which would have given us a choice...