test.pl

use Mojolicious::Lite;

any '/' => sub {
  my $c = shift;
  my $can_write = 1;
  my $buffer = '';
  my $done;
  # fake system that generates data every second
  my $r;
  $r = Mojo::IOLoop->recurring(1 => sub {
    $buffer .= "Some new content\n" unless $done;
    if ($can_write) {
      $can_write = 0;
      $c->write_chunk($buffer => sub { $can_write = 1 });
      $buffer = '';
      Mojo::IOLoop->remove($r) if $done;
    }
  });
  Mojo::IOLoop->timer(10 => sub { $done++ });
};

app->start;