The aim is to list all the essays for all the categories an essay belongs to, in the context of essay.lens in a koken.me project. As of Koken v0.7.1, the solution https://gist.github.com/bradleyboy/0b4c335141bb2d22634f crashes the page. So, instead, manually, the solution below (rinse and repeat for all the categories of your project)…

KOKEN - essays-categories-list.html

<koken:categories>
    <koken:loop>
        <koken:if data="category.id" equals="1">
            Also in <strong>{{ category.title }}</strong>
            <ul>
            <koken:load source="essays" filter:category="1">
                <koken:loop>
                    <li>
                        <koken:link>
                            {{ essay.title }}
                        </koken:link>
                    </li>
                </koken:loop>
            </koken:load>
            </ul>
        </koken:if>
        <koken:if data="category.id" equals="2">
            Also in <strong>{{ category.title }}</strong>
            <ul>
            <koken:load source="essays" filter:category="2">
                <koken:loop>
                    <li>
                        <koken:link>
                            {{ essay.title }}
                        </koken:link>
                    </li>
                </koken:loop>
            </koken:load>
            </ul>
        </koken:if>
        [etc etc etc]
    </koken:loop>
</koken:categories>

Problem fixed with v0.8.0 if I remember well, it's v0.9.2 at the time of writing of this comment, so I'm not deleting this for not breaking links to this, really.

I am doing a statistics project for https://www.the-essays.com/statistics-project
and I'm glad I've found your code. Even thought it's old but still helpful and relevant