use strict;
use warnings;
use PDF::API2;

my $doc = PDF::API2-> open( 'sample.pdf' );     # Assuming it to have at least 
                                                # 2 pages
$doc-> outlines
    -> outline
        -> dest( $doc-> openpage( 1 ))          # All this chaining is not
        -> title( '1st page')                   # really necessary, doing it
        -> parent                               # just for fun.
    -> outline
        -> title( '2nd page')
        -> open
        -> outline
            -> title( 'top of 2nd page' )
            -> dest( $doc-> openpage( 2 ), '-xyz' => [ 0, 0, 0 ])
            -> parent
        -> outline 
            -> title( '2nd page, 500 pts from top edge' )
            -> dest( $doc-> openpage( 2 ), '-xyz' => [ 0, 500, 0 ]);

$doc-> preferences( '-outlines' => 1 );
$doc-> saveas( 'sample+.pdf' );