[Answered ]-Filter in custom Django tag?

If you use the simple_tag decorator to write your custom tag, you should be able to use a filters on the arguments.

However, if you have written an advanced template tag, then you will need to do extra work to make "most"|add:"_people" use the filter as you want.

One work around, is to use the {% with %} tag to assign the result of the filter to a variable.

{% with panel_name="most"|add:"_people" %}
{% panel panel_name %}
{% endwith %}