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Ali Fatehi
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Custom WordPress plugin development

For when no off-the-shelf plugin does quite what you need — or one does, but brings ten times the surface area you asked for.

What you get

  • A custom plugin written to the WordPress coding standards
  • A settings screen in the admin built on the Settings API
  • REST endpoints where the data needs to be consumed elsewhere
  • Safe data migration and activation/deactivation routines
  • Technical documentation: the hooks and filters available for future work
  • Full source, unobfuscated, with no licence server

How it runs

  1. 1

    Define the scope precisely

    First we agree what the plugin does and, more importantly, what it does not. Most custom plugins get heavy because their scope opens up halfway through.

  2. 2

    Build on hooks, never on core edits

    No core files are touched. Everything goes through official actions and filters so a WordPress update breaks nothing.

  3. 3

    Test and document

    The plugin is tested across PHP and WordPress versions and ships with a technical README.

Signs you need a custom plugin

  • You have installed three plugins to do one simple job, each bringing ten features you did not want.
  • Your theme's functions.php has grown to a thousand lines and nobody will touch it.
  • The plugin you depend on is unmaintained and was last updated two years ago.
  • Your requirement is specific to your business and no general product exists for it.

How the code is written

No core edits, no direct modification of other plugins, and hooks exposed so the plugin itself can be extended later:

<?php
/**
 * Plugin Name: Acme Order Router
 * Requires PHP: 8.1
 */
 
declare( strict_types = 1 );
 
add_action( 'woocommerce_checkout_create_order', 'acme_assign_warehouse', 10, 2 );
 
function acme_assign_warehouse( WC_Order $order, array $data ): void {
    $region    = $order->get_shipping_state();
    $warehouse = acme_pick_warehouse( $region );
 
    // Public filter: the selection logic can be overridden later
    // without editing this file.
    $warehouse = apply_filters( 'acme_selected_warehouse', $warehouse, $order );
 
    $order->update_meta_data( '_acme_warehouse', $warehouse );
}

Two things in that short snippet matter: declare(strict_types=1), because PHP's weak typing is a source of silent bugs, and apply_filters, because a plugin that cannot be extended gets rewritten in six months.

Activation and data migration

Most serious plugin failures happen during activation and upgrade. Every plugin I write tracks a schema version and runs migrations step by step and reversibly — not a single dbDelta call and a hope.

Frequently asked questions

Why not just buy a plugin?

If an existing plugin does exactly what you need, buy it — I will tell you so and not charge for the conversation. A custom plugin makes sense when nothing exists, or when reaching your requirement means gluing three plugins together.

Do I own the code?

Yes. Full source is delivered, unencrypted, with no licence system and no dependency on any server of mine.

Will a WordPress update break it?

Because it only uses official APIs, that is unlikely. If a WordPress change breaks it directly, I fix it free for six months after delivery.

Can you modify a plugin I already have?

Yes, if its source is open. I do that as a separate companion plugin working through hooks, so updating the original does not wipe the work.

Related services

Not sure which one you need?

Just describe the problem. Working out which bucket it falls into is my job.

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