{% macro box(type, title, slim=False, caller=None) %}
<aside class="box{% if slim %} slim{% endif %} {{ type }}"><header>{{ title }}</header> {{ caller() }}</aside>
{% endmacro %}

{% macro avatar(from_, hash, caller=None) -%}
{%- if hash -%}
<div class="avatar" style="background-image: url('{{ url_for_avatar(from_, hash) }}');"></div>
{%- else -%}
{%- endif -%}
{%- endmacro %}