We are building a new site using Symfony2, and Assetic looks very promising for resource management, in particular for combining and processing all js/css files together aut
You can actually do the following:
In layout.html.twig (or whatever your layout is)
{% block stylesheets %}
{% stylesheets 'your_assets_here' %}
{% endstylesheets %}
{% endblock %}
And in any template that extends that layout:
{% block stylesheets %}
{{ parent() }}
{% stylesheets 'additional_assets_here' %}
{% endstylesheets %}
{% endblock %}
Then you wouldn't need to retype all the old assets as suggested by Nemanja Niljkovic