How to add a field to a WordPress Taxonomy page on the Roots stack

I'm working on a WordPress project at my day job. We needed to add an ACF (Advanced Custom Fields) field to a Taxonomy page, but we wanted to do it the "Roots" way.

It turns out it's very easy! Here's what I ended up doing:

Create a Taxonomies folder inside your app/Fields folder.

Add a php class with the name of your Taxonomy in Pascal case. For my project, I have a issue-type Taxonomy, so I named it IssueType.php

Then, inside the file, you need to need to:

1. Use the Taxonomies namespace
2. Add your structure as if it were a regular fields file except for adding this to the $fields array

->setLocation('taxonomy', '==', 'YOUR_TAXONOMY_GOES_HERE')

Here's the final file so you can use it as an example.

<?php

namespace App\Fields\Taxonomies;

use Log1x\AcfComposer\Field;
use StoutLogic\AcfBuilder\FieldsBuilder;

class IssueType extends Field
{
    public function fields()
    {
        $fields = new FieldsBuilder('issue_type_metadata');
        $fields
            ->setLocation('taxonomy', '==', 'issue-type')
            ->addGroup('issue_type_metadata')
            // your fields go here
            ->endGroup();

        return $fields->build();
    }
}