Plack/PSGI Ecosystem - bulknews.typepad.com

The picture might scare you like "holy cow that's a lot of layers!" but actually, No, PSGI interface is a Perl code reference that's executed inline, and a framework adapter is just a few lines of changes from their native CGI/mod_perl adapters. So it's usually an extra one or two method call stack and that could never be an overhead.

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