I added template_options method for convinience.

use Amon2::Lite;

__PACKAGE__->template_options(
  syntax => 'Kolon',
);

get '/' => sub {
  my $c = shift;
  $c->render('hoge', { foo => 'haga' });
};

__PACKAGE__->to_app();

__DATA__
@@ hoge
<: $foo :>