# server.pl
use Time::HiRes;
app->hook(before_dispatch => sub {
  app->defaults(request_start_time => [gettimeofday]);
});

# index.html.ep
% my $request_timer = begin
  <p>Page served in <%= Time::HiRes::tv_interval($request_start_time) %> seconds.</p>
% end
<%= $request_timer->() %>