mrwweb

Tracy Rotton

TatumCreative

Filter your posts (including custom post types) by your custom taxonomies, just like you can with WordPress’ native category filter.

TC Custom Taxonomy Filter

Filter your posts by your custom taxonomies.

Damian Gostomski

This plugin extends the default taxonomy functionality and extends it to users, while automating all the boilerplate code.
Once activated, you can register user taxonomies using the following code:
<pre><code>register_taxonomy('profession', 'user', array(
 'public' =>true,
 'labels' =>array(
 'name' =>'Professions',
 'singular_name' =>'Profession',
 'menu_name' =>'Professions',
 'search_items' =>'Search Professions',
 'popular_items' =>'Popular Professions',
 'all_items' =>'All Professions',
 'edit_item' =>'Edit Profession',
 'update_item' =>'Update Profession',
 'add_new_item' =>'Add New Profession',
 'new_item_name' =>'New Profession Name',
 'separate_items_with_commas'=>'Separate professions with commas',
 'add_or_remove_items' =>'Add or remove professions',
 'choose_from_most_used' =>'Choose from the most popular professions',
 ),
 'rewrite' =>array(
 'with_front' =>true,
 'slug' =>'author/profession',
 ),
 'capabilities' => array(
 'manage_terms' =>'edit_users',
 'edit_terms' =>'edit_users',
 'delete_terms' =>'edit_users',
 'assign_terms' =>'read',
 ),
));
</code></pre>
Read more about <a href="https://codex.wordpress.org/Function_Reference/register_taxonomy" rel="nofollow ugc">registering taxonomies in the codex</a> 
This is heavily inspired by previous work by <a href="http://justintadlock.com/archives/2011/10/20/custom-user-taxonomies-in-wordpress" rel="nofollow ugc">Justin Tadlock</a>

User Taxonomies

Simplify the process of adding support for custom taxonomies for Users. Just use register_taxonomy and everything else is taken care of.

TC Custom Taxonomy Filter vs User Taxonomies