Custom Fields (declarative filters)

Add custom fields to any plugin form — Job Form, Company Form, Candidate Profile, Application Form — with one add_filter call. The filter takes a single field-group schema; the plugin handles rendering, validation, persistence, REST exposure, and admin display.

The four filters

Filter	Form
wcb_job_form_fields	Post a Job (multi-step + single-page forms)
wcb_company_form_fields	Company profile editor
wcb_candidate_form_fields	Candidate profile editor
wcb_application_form_fields_groups	Apply to a job

All four use the same field-group schema — once you’ve learned one, you’ve learned all four.

Schema

A field group looks like this:

[
    'group_id'    => 'employer_screening',
    'group_label' => __( 'Screening Questions', 'wp-career-board' ),
    'fields'      => [
        [
            'key'         => 'years_experience',
            'label'       => __( 'Years of relevant experience', 'wp-career-board' ),
            'type'        => 'number',
            'required'    => true,
            'min'         => 0,
            'max'         => 60,
        ],
        [
            'key'         => 'visa_status',
            'label'       => __( 'Current visa status', 'wp-career-board' ),
            'type'        => 'select',
            'required'    => true,
            'options'     => [
                'us-citizen'    => 'US Citizen',
                'green-card'    => 'Green Card',
                'h1b'           => 'H-1B',
                'opt'           => 'OPT',
                'needs-sponsor' => 'Needs sponsorship',
            ],
        ],
        [
            'key'         => 'portfolio_url',
            'label'       => __( 'Portfolio URL', 'wp-career-board' ),
            'type'        => 'url',
            'required'    => false,
            'placeholder' => 'https://',
        ],
    ],
]

Field types

Type	Renders	Stored as
text	Single-line input	string
textarea	Multi-line textarea	string
email	Email input + validation	string
url	URL input + validation	string
number	Numeric input with min/max	int / float
select	Dropdown	string (option key)
radio	Radio button group	string (option key)
checkbox	Single boolean checkbox	'1' / ''
multi-checkbox	Multiple checkboxes	array of option keys
date	Date picker	YYYY-MM-DD string

Example: Add a “Portfolio URL” field to the candidate profile

add_filter( 'wcb_candidate_form_fields', function( $groups ) {
    $groups[] = [
        'group_id'    => 'links',
        'group_label' => __( 'Online presence', 'wp-career-board' ),
        'fields'      => [
            [
                'key'      => 'portfolio_url',
                'label'    => __( 'Portfolio URL', 'wp-career-board' ),
                'type'     => 'url',
                'required' => false,
            ],
            [
                'key'      => 'github_url',
                'label'    => __( 'GitHub profile URL', 'wp-career-board' ),
                'type'     => 'url',
                'required' => false,
            ],
        ],
    ];
    return $groups;
} );

After this filter is in place:

• The candidate profile editor renders both fields.
• The fields validate on save (URL format).
• Values persist as user meta _wcb_candidate_field_portfolio_url and _wcb_candidate_field_github_url.
• They appear in the candidate’s REST response on GET /wcb/v1/candidates/{id}.

Example: Add a screening question to the application form

add_filter( 'wcb_application_form_fields_groups', function( $groups, $job_id ) {
    $groups[] = [
        'group_id'    => 'screening',
        'group_label' => __( 'Quick screen', 'wp-career-board' ),
        'fields'      => [
            [
                'key'      => 'years_relevant',
                'label'    => __( 'Years of relevant experience', 'wp-career-board' ),
                'type'     => 'number',
                'required' => true,
            ],
            [
                'key'      => 'salary_expectation',
                'label'    => __( 'Salary expectation (USD/yr)', 'wp-career-board' ),
                'type'     => 'number',
                'required' => false,
            ],
        ],
    ];
    return $groups;
}, 10, 2 );

This adds the screening group to every job’s apply form. To scope to specific jobs, branch on $job_id inside the callback.

Per-job custom fields (Pro field builder)

The above filter applies globally. For per-job configuration without writing PHP, install Pro and use the Field Builder admin page — the builder writes the same data structure to the wcb_field_groups / wcb_field_definitions Pro tables and contributes to the same filters automatically.

Where the data appears

Custom field values appear:

• In the admin Edit Application screen — under a “Custom fields” section per group.
• In the bulk CSV export — one column per field key.
• In the REST API — under the custom_fields key of the job / company / candidate / application response.
• In templates — via the Icon::svg() style helpers and direct postmeta reads (get_post_meta($id, '_wcb_application_field_<key>', true)).

Persistence keys

Per surface:

Filter	Stored where	Meta key prefix
wcb_job_form_fields	wp_postmeta (job)	_wcb_job_field_<key>
wcb_company_form_fields	wp_postmeta (company)	_wcb_company_field_<key>
wcb_candidate_form_fields	wp_usermeta (candidate)	_wcb_candidate_field_<key>
wcb_application_form_fields_groups	wp_postmeta (application)	_wcb_application_field_<key>

A bundle of all field values also lives at the corresponding _wcb_*_fields_bundle key for one-shot reads.