in reply to is Plack really necessary?
Well, at least one of those frameworks won't work without Plack. Surely, you see that, don't you?
Plack is what we call a "framework for frameworks", not exactly targeted at your "average" Perl developer, but there's nothing stopping them from using Plack in its barebones form.
As an exercise, take a look at Plack's reverse dependencies
Have fun, as always!
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