WordPress Plugin Development: Complete Beginner to Advanced Guide 2026

After building over 30 custom WordPress plugins—from simple utility tools to complex e-commerce integrations—I've developed a reliable approach to plugin development that keeps code maintainable and secure. In this guide, I'll walk you through everything from your first plugin file to publishing on the WordPress.org repository.

Why Build Custom WordPress Plugins?

WordPress powers over 43% of all websites, and plugins are the primary way to extend its functionality. Building custom plugins lets you:

• Solve specific business problems that no existing plugin addresses
• Avoid plugin bloat by writing only the code you need
• Control quality and security instead of trusting third-party code
• Create commercial products for the WordPress marketplace
• Contribute to the community through open-source development

The WordPress plugin ecosystem has over 60,000 free plugins, yet businesses constantly need custom solutions that don't exist off the shelf.

WordPress Plugin Structure

Every WordPress plugin starts with a single PHP file containing a plugin header comment. Here's the minimum viable plugin:

Basic Plugin File

Create a new directory in wp-content/plugins/ and add your main plugin file:

<?php
/**
 * Plugin Name: My Custom Plugin
 * Plugin URI: https://yoursite.com/my-custom-plugin
 * Description: A brief description of what the plugin does.
 * Version: 1.0.0
 * Author: Your Name
 * Author URI: https://yoursite.com
 * License: GPL v2 or later
 * License URI: https://www.gnu.org/licenses/gpl-2.0.html
 * Text Domain: my-custom-plugin
 * Domain Path: /languages
 * Requires at least: 6.0
 * Requires PHP: 8.0
 */

// Prevent direct file access
if (!defined('ABSPATH')) {
    exit;
}

// Define plugin constants
define('MCP_VERSION', '1.0.0');
define('MCP_PLUGIN_DIR', plugin_dir_path(__FILE__));
define('MCP_PLUGIN_URL', plugin_dir_url(__FILE__));

Recommended Directory Structure

For anything beyond a trivial plugin, organize your files like this:

my-custom-plugin/
├── my-custom-plugin.php      # Main plugin file
├── readme.txt                # WordPress.org readme
├── uninstall.php             # Cleanup on uninstall
├── includes/
│   ├── class-plugin-core.php # Main plugin class
│   ├── class-admin.php       # Admin functionality
│   └── class-public.php      # Frontend functionality
├── admin/
│   ├── css/
│   ├── js/
│   └── views/                # Admin page templates
├── public/
│   ├── css/
│   └── js/
├── languages/                # Translation files
└── templates/                # Public-facing templates

Understanding Hooks: Actions and Filters

Hooks are the backbone of WordPress plugin development. They let you inject your code into WordPress at specific points without modifying core files.

Actions

Actions let you execute code at specific points in the WordPress lifecycle:

// Add a custom message after each post
add_action('the_content', 'mcp_add_post_footer');

function mcp_add_post_footer($content) {
    if (is_single() && is_main_query()) {
        $footer = '<div class="post-footer">';
        $footer .= '<p>Thanks for reading! Share this post with your network.</p>';
        $footer .= '</div>';
        $content .= $footer;
    }
    return $content;
}

Common actions you'll use frequently:

Action Hook	When It Fires
init	After WordPress loads but before headers are sent
admin_init	On every admin page load
wp_enqueue_scripts	When enqueueing frontend scripts/styles
admin_enqueue_scripts	When enqueueing admin scripts/styles
save_post	When a post is saved or updated
wp_ajax_{action}	When handling an AJAX request (logged-in users)
wp_ajax_nopriv_{action}	When handling an AJAX request (non-logged-in users)

Filters

Filters modify data before WordPress uses or displays it:

// Modify the excerpt length
add_filter('excerpt_length', 'mcp_custom_excerpt_length');

function mcp_custom_excerpt_length($length) {
    return 30; // 30 words instead of default 55
}

// Add custom CSS classes to the body tag
add_filter('body_class', 'mcp_custom_body_classes');

function mcp_custom_body_classes($classes) {
    if (is_page_template('templates/landing.php')) {
        $classes[] = 'landing-page';
        $classes[] = 'no-sidebar';
    }
    return $classes;
}

Priority and Accepted Arguments

Control execution order and the number of arguments your callback receives:

// Lower priority number = runs earlier (default is 10)
add_action('init', 'mcp_early_init', 5);
add_action('init', 'mcp_late_init', 20);

// Accept multiple arguments with the fourth parameter
add_filter('the_title', 'mcp_modify_title', 10, 2);

function mcp_modify_title($title, $post_id) {
    $post = get_post($post_id);
    if ($post && $post->post_type === 'product') {
        return '🛒 ' . $title;
    }
    return $title;
}

Building an Admin Settings Page

Most plugins need a settings page. Here's how to create one properly using the WordPress Settings API:

Register the Menu and Settings

class MCP_Admin {

    public function __construct() {
        add_action('admin_menu', array($this, 'add_admin_menu'));
        add_action('admin_init', array($this, 'register_settings'));
    }

    public function add_admin_menu() {
        add_options_page(
            'My Plugin Settings',     // Page title
            'My Plugin',              // Menu title
            'manage_options',         // Capability required
            'my-custom-plugin',       // Menu slug
            array($this, 'settings_page') // Callback
        );
    }

    public function register_settings() {
        register_setting(
            'mcp_settings_group',     // Option group
            'mcp_settings',           // Option name
            array($this, 'sanitize_settings') // Sanitization callback
        );

        add_settings_section(
            'mcp_general_section',
            'General Settings',
            array($this, 'section_description'),
            'my-custom-plugin'
        );

        add_settings_field(
            'mcp_api_key',
            'API Key',
            array($this, 'api_key_field'),
            'my-custom-plugin',
            'mcp_general_section'
        );

        add_settings_field(
            'mcp_enable_feature',
            'Enable Feature',
            array($this, 'enable_feature_field'),
            'my-custom-plugin',
            'mcp_general_section'
        );
    }

    public function sanitize_settings($input) {
        $sanitized = array();
        $sanitized['api_key'] = sanitize_text_field($input['api_key'] ?? '');
        $sanitized['enable_feature'] = isset($input['enable_feature']) ? 1 : 0;
        return $sanitized;
    }

    public function section_description() {
        echo '<p>Configure your plugin settings below.</p>';
    }

    public function api_key_field() {
        $options = get_option('mcp_settings');
        $value = $options['api_key'] ?? '';
        echo '<input type="text" name="mcp_settings[api_key]" value="' . esc_attr($value) . '" class="regular-text">';
    }

    public function enable_feature_field() {
        $options = get_option('mcp_settings');
        $checked = isset($options['enable_feature']) && $options['enable_feature'] ? 'checked' : '';
        echo '<input type="checkbox" name="mcp_settings[enable_feature]" value="1" ' . $checked . '>';
    }

    public function settings_page() {
        if (!current_user_can('manage_options')) {
            return;
        }
        ?>
        <div class="wrap">
            <h1><?php echo esc_html(get_admin_page_title()); ?></h1>
            <form action="options.php" method="post">
                <?php
                settings_fields('mcp_settings_group');
                do_settings_sections('my-custom-plugin');
                submit_button('Save Settings');
                ?>
            </form>
        </div>
        <?php
    }
}

new MCP_Admin();

Registering Custom Post Types

Custom post types are one of the most powerful WordPress features. Here's how to register one properly:

add_action('init', 'mcp_register_portfolio_post_type');

function mcp_register_portfolio_post_type() {
    $labels = array(
        'name'               => 'Portfolio',
        'singular_name'      => 'Project',
        'menu_name'          => 'Portfolio',
        'add_new'            => 'Add New Project',
        'add_new_item'       => 'Add New Project',
        'edit_item'          => 'Edit Project',
        'new_item'           => 'New Project',
        'view_item'          => 'View Project',
        'search_items'       => 'Search Projects',
        'not_found'          => 'No projects found',
        'not_found_in_trash' => 'No projects in trash',
    );

    $args = array(
        'labels'             => $labels,
        'public'             => true,
        'publicly_queryable' => true,
        'show_ui'            => true,
        'show_in_menu'       => true,
        'show_in_rest'       => true, // Enable Gutenberg editor
        'query_var'          => true,
        'rewrite'            => array('slug' => 'portfolio'),
        'capability_type'    => 'post',
        'has_archive'        => true,
        'hierarchical'       => false,
        'menu_position'      => 5,
        'menu_icon'          => 'dashicons-portfolio',
        'supports'           => array(
            'title',
            'editor',
            'thumbnail',
            'excerpt',
            'custom-fields',
            'revisions',
        ),
    );

    register_post_type('portfolio', $args);
}

Adding a Custom Taxonomy

add_action('init', 'mcp_register_project_type_taxonomy');

function mcp_register_project_type_taxonomy() {
    $labels = array(
        'name'              => 'Project Types',
        'singular_name'     => 'Project Type',
        'search_items'      => 'Search Project Types',
        'all_items'         => 'All Project Types',
        'parent_item'       => 'Parent Project Type',
        'parent_item_colon' => 'Parent Project Type:',
        'edit_item'         => 'Edit Project Type',
        'update_item'       => 'Update Project Type',
        'add_new_item'      => 'Add New Project Type',
        'new_item_name'     => 'New Project Type Name',
        'menu_name'         => 'Project Types',
    );

    register_taxonomy('project_type', 'portfolio', array(
        'labels'            => $labels,
        'hierarchical'      => true,
        'public'            => true,
        'show_ui'           => true,
        'show_in_rest'      => true,
        'show_admin_column' => true,
        'rewrite'           => array('slug' => 'project-type'),
    ));
}

Enqueueing Scripts and Styles

Never hardcode <script> or <link> tags. Use WordPress's enqueue system for proper dependency management:

add_action('wp_enqueue_scripts', 'mcp_enqueue_frontend_assets');

function mcp_enqueue_frontend_assets() {
    // Enqueue a CSS file
    wp_enqueue_style(
        'mcp-styles',
        MCP_PLUGIN_URL . 'public/css/styles.css',
        array(), // Dependencies
        MCP_VERSION
    );

    // Enqueue a JavaScript file with jQuery dependency
    wp_enqueue_script(
        'mcp-scripts',
        MCP_PLUGIN_URL . 'public/js/scripts.js',
        array('jquery'),
        MCP_VERSION,
        true // Load in footer
    );

    // Pass PHP data to JavaScript
    wp_localize_script('mcp-scripts', 'mcpData', array(
        'ajaxUrl'  => admin_url('admin-ajax.php'),
        'nonce'    => wp_create_nonce('mcp_nonce'),
        'siteUrl'  => home_url(),
        'strings'  => array(
            'confirm' => __('Are you sure?', 'my-custom-plugin'),
            'success' => __('Changes saved.', 'my-custom-plugin'),
        ),
    ));
}

// Admin-only scripts
add_action('admin_enqueue_scripts', 'mcp_enqueue_admin_assets');

function mcp_enqueue_admin_assets($hook) {
    // Only load on our plugin's settings page
    if ($hook !== 'settings_page_my-custom-plugin') {
        return;
    }

    wp_enqueue_style(
        'mcp-admin-styles',
        MCP_PLUGIN_URL . 'admin/css/admin-styles.css',
        array(),
        MCP_VERSION
    );
}

Handling AJAX Requests

AJAX lets your plugin communicate with the server without page reloads:

PHP Handler

// For logged-in users
add_action('wp_ajax_mcp_save_data', 'mcp_handle_save_data');
// For non-logged-in users (only if needed)
add_action('wp_ajax_nopriv_mcp_save_data', 'mcp_handle_save_data');

function mcp_handle_save_data() {
    // Verify nonce for security
    if (!check_ajax_referer('mcp_nonce', 'nonce', false)) {
        wp_send_json_error(array(
            'message' => 'Security check failed.'
        ), 403);
    }

    // Check user capabilities
    if (!current_user_can('edit_posts')) {
        wp_send_json_error(array(
            'message' => 'Insufficient permissions.'
        ), 403);
    }

    // Sanitize input data
    $title = sanitize_text_field($_POST['title'] ?? '');
    $content = wp_kses_post($_POST['content'] ?? '');

    if (empty($title)) {
        wp_send_json_error(array(
            'message' => 'Title is required.'
        ));
    }

    // Process the data
    $post_id = wp_insert_post(array(
        'post_title'   => $title,
        'post_content' => $content,
        'post_status'  => 'draft',
        'post_type'    => 'post',
    ));

    if (is_wp_error($post_id)) {
        wp_send_json_error(array(
            'message' => $post_id->get_error_message()
        ));
    }

    wp_send_json_success(array(
        'message' => 'Post created successfully.',
        'post_id' => $post_id,
    ));
}

JavaScript AJAX Call

jQuery(document).ready(function($) {
    $('#mcp-save-form').on('submit', function(e) {
        e.preventDefault();

        var $button = $(this).find('button[type="submit"]');
        $button.prop('disabled', true).text('Saving...');

        $.ajax({
            url: mcpData.ajaxUrl,
            type: 'POST',
            data: {
                action: 'mcp_save_data',
                nonce: mcpData.nonce,
                title: $('#post-title').val(),
                content: $('#post-content').val()
            },
            success: function(response) {
                if (response.success) {
                    alert(response.data.message);
                } else {
                    alert('Error: ' + response.data.message);
                }
            },
            error: function() {
                alert('Request failed. Please try again.');
            },
            complete: function() {
                $button.prop('disabled', false).text('Save');
            }
        });
    });
});

Plugin Security Best Practices

Security is non-negotiable in plugin development. Follow these practices on every project:

Sanitize All Input

// Text fields
$name = sanitize_text_field($_POST['name']);

// Email addresses
$email = sanitize_email($_POST['email']);

// URLs
$url = esc_url_raw($_POST['website']);

// Rich text content (allows safe HTML)
$content = wp_kses_post($_POST['content']);

// Integer values
$count = absint($_POST['count']);

// File names
$filename = sanitize_file_name($_POST['filename']);

Escape All Output

// In HTML context
echo esc_html($user_input);

// In HTML attributes
echo '<input value="' . esc_attr($value) . '">';

// In URLs
echo '<a href="' . esc_url($link) . '">Click</a>';

// In JavaScript
echo '<script>var name = ' . wp_json_encode($name) . ';</script>';

// Allow specific HTML tags
echo wp_kses($content, array(
    'a'      => array('href' => array(), 'title' => array()),
    'strong' => array(),
    'em'     => array(),
));

Use Nonces for Form Verification

// In your form template
wp_nonce_field('mcp_save_action', 'mcp_nonce');

// In your form handler
if (!isset($_POST['mcp_nonce']) || !wp_verify_nonce($_POST['mcp_nonce'], 'mcp_save_action')) {
    wp_die('Security check failed.');
}

Check User Capabilities

// Before performing admin actions
if (!current_user_can('manage_options')) {
    wp_die('You do not have permission to access this page.');
}

// Before editing a specific post
if (!current_user_can('edit_post', $post_id)) {
    wp_die('You cannot edit this post.');
}

Plugin Activation, Deactivation, and Uninstall

Handle the full plugin lifecycle properly:

// Activation hook - runs once when plugin is activated
register_activation_hook(__FILE__, 'mcp_activate');

function mcp_activate() {
    // Create custom database tables
    global $wpdb;
    $table_name = $wpdb->prefix . 'mcp_logs';
    $charset_collate = $wpdb->get_charset_collate();

    $sql = "CREATE TABLE $table_name (
        id bigint(20) NOT NULL AUTO_INCREMENT,
        user_id bigint(20) NOT NULL,
        action varchar(100) NOT NULL,
        details text,
        created_at datetime DEFAULT CURRENT_TIMESTAMP,
        PRIMARY KEY (id),
        KEY user_id (user_id),
        KEY action (action)
    ) $charset_collate;";

    require_once ABSPATH . 'wp-admin/includes/upgrade.php';
    dbDelta($sql);

    // Set default options
    add_option('mcp_settings', array(
        'api_key'        => '',
        'enable_feature' => 0,
    ));

    // Register custom post type and flush rewrite rules
    mcp_register_portfolio_post_type();
    flush_rewrite_rules();
}

// Deactivation hook - runs when plugin is deactivated
register_deactivation_hook(__FILE__, 'mcp_deactivate');

function mcp_deactivate() {
    // Clear scheduled events
    $timestamp = wp_next_scheduled('mcp_daily_cleanup');
    if ($timestamp) {
        wp_unschedule_event($timestamp, 'mcp_daily_cleanup');
    }

    flush_rewrite_rules();
}

Create an uninstall.php file in your plugin root to clean up when the plugin is deleted:

<?php
// uninstall.php
if (!defined('WP_UNINSTALL_PLUGIN')) {
    exit;
}

// Remove plugin options
delete_option('mcp_settings');

// Remove custom database tables
global $wpdb;
$wpdb->query("DROP TABLE IF EXISTS {$wpdb->prefix}mcp_logs");

// Remove user meta
delete_metadata('user', 0, 'mcp_user_preference', '', true);

// Clear any cached data
wp_cache_flush();

Using OOP for Better Plugin Architecture

For maintainable plugins, use object-oriented architecture with an autoloader:

<?php
// Main plugin file: my-custom-plugin.php

if (!defined('ABSPATH')) {
    exit;
}

// Autoloader
spl_autoload_register(function ($class) {
    $prefix = 'MCP\\';
    $base_dir = MCP_PLUGIN_DIR . 'includes/';

    $len = strlen($prefix);
    if (strncmp($prefix, $class, $len) !== 0) {
        return;
    }

    $relative_class = substr($class, $len);
    $file = $base_dir . 'class-' . strtolower(str_replace('\\', '-', $relative_class)) . '.php';

    if (file_exists($file)) {
        require $file;
    }
});

// Initialize the plugin
add_action('plugins_loaded', function () {
    MCP\Plugin::get_instance();
});

<?php
// includes/class-plugin.php
namespace MCP;

class Plugin {

    private static $instance = null;

    public static function get_instance() {
        if (null === self::$instance) {
            self::$instance = new self();
        }
        return self::$instance;
    }

    private function __construct() {
        $this->load_dependencies();
        $this->define_admin_hooks();
        $this->define_public_hooks();
    }

    private function load_dependencies() {
        // Dependencies loaded via autoloader
    }

    private function define_admin_hooks() {
        $admin = new Admin();
        add_action('admin_menu', array($admin, 'add_menu_pages'));
        add_action('admin_init', array($admin, 'register_settings'));
        add_action('admin_enqueue_scripts', array($admin, 'enqueue_assets'));
    }

    private function define_public_hooks() {
        $public = new Frontend();
        add_action('wp_enqueue_scripts', array($public, 'enqueue_assets'));
        add_filter('the_content', array($public, 'modify_content'));
    }
}

Adding Shortcodes

Shortcodes let users embed plugin output anywhere in their content:

add_shortcode('mcp_contact_form', 'mcp_render_contact_form');

function mcp_render_contact_form($atts) {
    $atts = shortcode_atts(array(
        'title'       => 'Contact Us',
        'email'       => get_option('admin_email'),
        'button_text' => 'Send Message',
    ), $atts, 'mcp_contact_form');

    ob_start();
    ?>
    <div class="mcp-contact-form">
        <h3><?php echo esc_html($atts['title']); ?></h3>
        <form method="post" class="mcp-form">
            <?php wp_nonce_field('mcp_contact', 'mcp_contact_nonce'); ?>
            <p>
                <label for="mcp-name">Name</label>
                <input type="text" id="mcp-name" name="mcp_name" required>
            </p>
            <p>
                <label for="mcp-email">Email</label>
                <input type="email" id="mcp-email" name="mcp_email" required>
            </p>
            <p>
                <label for="mcp-message">Message</label>
                <textarea id="mcp-message" name="mcp_message" rows="5" required></textarea>
            </p>
            <p>
                <button type="submit"><?php echo esc_html($atts['button_text']); ?></button>
            </p>
        </form>
    </div>
    <?php
    return ob_get_clean();
}

Usage in WordPress editor: [mcp_contact_form title="Get in Touch" button_text="Submit"]

Scheduling Cron Jobs

Use WordPress cron for recurring tasks like sending reports, cleaning data, or syncing with external APIs:

// Schedule the event on plugin activation
register_activation_hook(__FILE__, 'mcp_schedule_events');

function mcp_schedule_events() {
    if (!wp_next_scheduled('mcp_daily_cleanup')) {
        wp_schedule_event(time(), 'daily', 'mcp_daily_cleanup');
    }
}

// Define the cron callback
add_action('mcp_daily_cleanup', 'mcp_run_daily_cleanup');

function mcp_run_daily_cleanup() {
    global $wpdb;
    $table = $wpdb->prefix . 'mcp_logs';

    // Delete logs older than 30 days
    $wpdb->query(
        $wpdb->prepare(
            "DELETE FROM $table WHERE created_at < %s",
            date('Y-m-d H:i:s', strtotime('-30 days'))
        )
    );

    // Log the cleanup
    error_log('MCP: Daily cleanup completed at ' . current_time('mysql'));
}

// Add custom cron schedule
add_filter('cron_schedules', 'mcp_add_cron_interval');

function mcp_add_cron_interval($schedules) {
    $schedules['fifteen_minutes'] = array(
        'interval' => 900,
        'display'  => 'Every Fifteen Minutes',
    );
    return $schedules;
}

Publishing to the WordPress Plugin Repository

Once your plugin is ready, submit it to WordPress.org:

Create a Proper readme.txt

=== My Custom Plugin ===
Contributors: yourusername
Tags: utility, custom post types, admin tools
Requires at least: 6.0
Tested up to: 6.7
Requires PHP: 8.0
Stable tag: 1.0.0
License: GPLv2 or later
License URI: https://www.gnu.org/licenses/gpl-2.0.html

Short description of the plugin (150 characters max).

== Description ==

Detailed description of your plugin. Explain the features,
use cases, and why someone should install it.

= Features =

* Feature one description
* Feature two description
* Feature three description

== Installation ==

1. Upload the plugin files to `/wp-content/plugins/my-custom-plugin`
2. Activate the plugin through the 'Plugins' screen in WordPress
3. Configure the plugin via Settings → My Plugin

== Frequently Asked Questions ==

= How do I configure the plugin? =

Navigate to Settings → My Plugin in your WordPress admin.

= Does this work with WooCommerce? =

Yes, the plugin is fully compatible with WooCommerce 8.0+.

== Changelog ==

= 1.0.0 =
* Initial release

== Upgrade Notice ==

= 1.0.0 =
Initial release of My Custom Plugin.

Submission Checklist

Before submitting, verify:

• No security vulnerabilities (sanitization, escaping, nonces)
• Plugin follows WordPress coding standards
• All strings are translatable using __() and _e()
• Plugin works with the latest WordPress version
• readme.txt is properly formatted
• No premium upsell or external service calls without disclosure
• GPL-compatible license
• No third-party code without proper attribution

Submit at WordPress Plugin Directory.

Debugging WordPress Plugins

Use these techniques to debug during development:

// Enable WordPress debug mode in wp-config.php
define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);    // Log errors to wp-content/debug.log
define('WP_DEBUG_DISPLAY', false); // Don't show errors on screen
define('SCRIPT_DEBUG', true);     // Use unminified core scripts

// Custom debug logging function
function mcp_log($message, $data = null) {
    if (!defined('WP_DEBUG') || !WP_DEBUG) {
        return;
    }

    $log_entry = '[MCP ' . current_time('Y-m-d H:i:s') . '] ' . $message;

    if ($data !== null) {
        $log_entry .= ' | Data: ' . print_r($data, true);
    }

    error_log($log_entry);
}

// Usage
mcp_log('Processing order', array('order_id' => 123, 'status' => 'pending'));

Install the Query Monitor plugin for detailed debugging of hooks, queries, HTTP requests, and more during development.

FAQ

How long does it take to learn WordPress plugin development?

If you know PHP basics, you can build a simple plugin in a few hours. Building production-ready plugins with proper architecture, security, and testing takes a few months of practice. Start with small utility plugins and gradually increase complexity.

Should I use OOP or procedural PHP for plugins?

For anything beyond a simple single-file plugin, use OOP. Classes provide better organization, avoid function name collisions, and make your code easier to test and maintain. The singleton pattern shown in this guide is a common starting point.

How do I update my plugin without breaking existing installations?

Use version checks and database migration patterns. Store a version number in the options table and compare it on plugins_loaded. Run upgrade routines when the stored version is lower than the current version. Never remove database columns or options without a deprecation period.

Can I use Composer in WordPress plugins?

Yes, but scope your dependencies to avoid conflicts with other plugins using the same libraries. Tools like PHP-Scoper or Strauss prefix namespaces to prevent autoloader collisions. This is especially important for popular libraries like Guzzle or Carbon.

What's the difference between a plugin and a must-use plugin?

Regular plugins can be activated and deactivated from the admin dashboard. Must-use plugins (mu-plugins) are placed in wp-content/mu-plugins/ and are always active—they cannot be deactivated without removing the file. Use mu-plugins for site-critical functionality that should never be accidentally disabled.

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Building WordPress plugins is one of the most valuable skills in the WordPress ecosystem. Start with the basics covered in this guide, and you'll be creating professional-grade plugins in no time. Have questions? Feel free to reach out.