timber-acf-pro-fix.php

<?php

# include this file in theme's functions.php

namespace Timber {

    /**
     * Proxy \get_post_meta to ACF get_field function
     *
     * @param $id
     * @param $field_name
     * @return mixed
     */
    function get_post_meta( $id, $field_name )
    {
        if (function_exists('get_field')) {
            return get_field($field_name, $id);
        }

        return \get_post_meta($id, $field_name);
    }
}