twigplugin.php

<?php 

kirby::$handlers['template'] = function($kirby, $page, $data = array()) {

  require_once(__DIR__ . DS . 'vendor' . DS . 'autoload.php');  

  $loader = new Twig_Loader_Filesystem($kirby->roots()->templates());
  $twig   = new Twig_Environment($loader, array(
    'cache' => false
  ));

  $data = array_merge(tpl::$data, array(
    'kirby' => $kirby,
    'site'  => $kirby->site(),
    'pages' => $kirby->site()->children(),
    'page'  => $page
  ), $page->templateData(), $data, $kirby->controller($page, $data));

  return $twig->render(basename($page->templateFile()), $data);

};

@shiftsave You might not need it anymore after close to one year, but for the record I made a Twig template component for Kirby 2.3: https://github.com/fvsch/kirby-twig
(And for other PHP templating engines, I guess it’s an okay enough example to help get people started.)