gistfile1.pl

use Plack::Builder;
use Plack::App::Proxy;

my $proxy = Plack::App::Proxy->new(
  remote => "http://dev.office.xerox.com",
  preserve_host_header => 1,
);

builder {
  mount "/" => sub {
    my $env = shift;
    $env->{HTTP_HOST} =~ s/:\d+$//;
    $proxy->($env);
  };
  mount "/foo" => sub {
    [200, ['Content-type', 'text/plain'], ['This page served via plack']];
  };
};