Just remove the sub name. Instead of returning a sub reference, you are declaring a sub. Since you aren’t using $env and the return is implicit, just as the the return of the sub is, you can even shorten it to this (again, some style room so do what you like or find most readable)– 

sub {
    [
     200,
     [ 'Content-Type' => 'text/plain' ],
     [ "Hello World" ]
    ];
}

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In reply to Re: plackup problem by Your Mother
in thread plackup problem by Perler#2

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