fibonacci_app.pl

use Mojolicious::Lite;
use Mojo::IOLoop;

sub fib { $_[0] < 2 ? 1 : fib($_[0] - 2) + fib($_[0] - 1) }

get '/fibonacci' => sub {
  my $c = shift;

  $c->inactivity_timeout(300);

  Mojo::IOLoop->subprocess(
    sub { fib(35) },
    sub {
      my ($subprocess, $err, $result) = @_;
      $c->render(text => "The result of fib(35) is $result.");
    }
  );
};

app->start;