bash$ plackup -e 'use warnings; INIT{ warn "foo"; }; sub { warn "here"; return [200, [], []] };'
 Too late to run INIT block at (eval 7) line 1.
 HTTP::Server::PSGI: Accepting connections at http://0:5000/
 here at (eval 7) line 1.
 127.0.0.1 - - [20/Nov/2014:14:18:08 +0200] "GET / HTTP/1.1" 200 - "-" "Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:33.0) Gecko/20100101 Firefox/33.0"


##</code><code>##

use Init::Queue sub { 
    get_dbh(); 
    load_file();
    build_cache(); 
}; # postpone till explicitly called

##</code><code>##

Init::Queue->startup(); 
# this executes all startup blocks,
# in order of appearance