How to implement the "blog functionality" in WP using Timber and Twig?

Question

I'm using timber and twig with wordpress trying to get the good old blog functionality. Problem is that i do not receive any posts when using the index.php (which is correct, right?)

When running this in index.php and assign a posts page in admin i get no posts. When running same code in a custom template file i get the posts. What on earth am i doing wrong here?

Index.php (no posts returned, wordpress predefined "blog" template, assigned as the posts page in settings)

<?php

/* File: index.php */

$context = Timber::context();

$args = array (
  'post_type' => 'post',
  'numberposts' => -1
);

$context['posts'] = Timber::get_posts($args);
$template = array('pages/news/index.twig');

Timber::render($template, $context);

News.php (posts returned, file assigned as a template for a page in wp-admin)

<?php

/* Template Name: News */

$context = Timber::context();

$args = array (
  'post_type' => 'post',
  'numberposts' => -1
);

$context['posts'] = Timber::get_posts($args);
$template = array('pages/news/index.twig');

Timber::render($template, $context);

index.twig (template)

{% if posts %}
  {% for p in posts %}
    {{ p|dump }}
  {% endfor %}
{% endif %}