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Shahid Malla

WHMCS development

WHMCS Development Services

WHMCS is a billing, client management and automation platform used by hosting companies and online service businesses. I am Shahid Malla, a freelance WHMCS developer. I build custom modules and integrations for it, move it between servers and versions, and audit its security, with every change kept in supported folders so it survives upgrades.

Discuss your WHMCS project Book a free scoping call

Free scoping call of about 30 minutes · written quote within one business day · two weeks of support after delivery

By Shahid Malla, AI agent and AI chat developer, full-stack developer · Updated

Hire and move

Bring in a developer for a defined job, or move an existing system without losing data.

Build and extend

Add what WHMCS does not ship, in a way that survives upgrades.

Protect and maintain

Keep WHMCS safe, patched and working after launch.

What is WHMCS?

WHMCS is a billing, client management and automation platform used by hosting companies and online service businesses to take orders, send invoices, collect payments, set up services and answer support tickets. It is a PHP and MySQL application that runs on your own server, with a client area for customers and an admin area for staff. The official documentation is at docs.whmcs.com, and my guide what WHMCS is and how it differs from cPanel covers the basics.

I am a freelance WHMCS expert. I have worked on WHMCS for more than 13 years and have built more than 200 custom WHMCS modules. This page explains what separates WHMCS work from ordinary web development, how to pick a developer, and which of my services fits which problem.

What does a WHMCS specialist do that a general PHP developer usually does not?

A WHMCS specialist knows which changes WHMCS supports and which ones the next upgrade will erase. A good PHP developer can write the code. The usual failure is code placed where WHMCS does not expect it, or code that ignores how WHMCS processes payments and automation.

AreaWhat a specialist handles
Supported foldersCustom code goes in modules/, includes/hooks/ and a custom template folder. Core files stay untouched, so an upgrade does not undo the work.
HooksA function registered with add_hook runs on events such as invoice creation, client registration or a client area page load, with no core change.
Module typesProvisioning, addon, payment gateway, registrar, fraud, widget and notification modules each have their own file layout and function names.
Gateway callbacksAn invoice is only paid when the callback says so. It must check the invoice and transaction, verify the signature and survive duplicate notifications.
LicensingA WHMCS license is tied to the server's IP address and domain. Moves, IP changes and ionCube-encoded files all need to be planned around it.
CronInvoice generation, reminders, suspensions and terminations all run from one cron job. If it stops, billing stops quietly.

How do I choose a WHMCS developer?

Choose a developer who can answer yes to the five checks below and will put the answers in writing before work starts. If you are ready to hire a WHMCS developer, that page covers how I scope, price and hand over the work.

  • Staging first. Will they build and test on a copy, with test gateway keys, before anything reaches live billing?
  • No core edits. Will all custom code sit in modules, hooks and template folders, so you can upgrade WHMCS later?
  • Version compatibility. Do they state which WHMCS and PHP versions the work was tested on, and what to retest after an upgrade?
  • Code ownership. Is it clear who owns the code, whether you receive the source, and whether any of it is encoded?
  • Documentation. Will you get written notes on what changed, where the files are and how to undo it?

What do I do, and what do I not do?

I build, move, secure and maintain WHMCS installations, always inside the structure WHMCS supports.

What I do

  • Set up new installations and migrate existing ones between servers and versions.
  • Write custom modules, hooks, gateway integrations and API links, including a WHMCS live chat integration that knows which client is signed in.
  • Restyle the client area, order forms and email templates in a safe child or custom theme.
  • Review installations for security problems and fix what the review finds.

What I do not do

  • Edit WHMCS core files.
  • Install or repair nulled, cracked or unlicensed WHMCS copies, modules or themes.
  • Write code that stores card numbers or card security codes.
  • Work directly on a live system before the same change has been proven in staging.

Which WHMCS service should I start with?

Start with the problem that costs you money today. If invoices or emails are failing right now, begin with the troubleshooting guide or a support plan. If you are unsure, the free scoping call exists to answer exactly that question.

One disclosure. I am the founder of WHMCSPilot.com, which sells premium WHMCS modules and themes. If an existing module already does what you need, I will tell you so rather than quote a custom build, and I will say if the one I suggest is mine.

Who this is for

  • Hosting companies and resellers who run their business on WHMCS
  • Agencies, SaaS owners and service businesses that bill clients through WHMCS
  • Owners of a WHMCS installation that has outgrown its original setup
  • Teams that need a module, gateway or integration WHMCS does not ship

What is included

  • Free scoping call of about 30 minutes and a quote within one business day
  • All work done in a staging copy and deployed only when you approve
  • Custom code kept in supported locations: modules, hooks and template folders
  • A short progress update every working day while the job is active
  • Written handover documentation your next developer can follow
  • Two weeks of post-delivery support for anything that surfaces

How the work runs

  1. 1

    Scope

    A free call of about 30 minutes. I ask what is broken or missing, which WHMCS and PHP versions you run, and what must not change. A written quote follows within one business day.

  2. 2

    Stage

    I work on a staging copy of your installation, with test gateway keys and a copy of your data, so nothing touches live billing until the work is proven.

  3. 3

    Build and test

    I build in the supported folders and test the real paths: orders, invoices, renewals, failed payments and the cron run. You get a short update each working day.

  4. 4

    Hand over

    I deploy when you approve, then give you written documentation covering what changed, where the files are and how to undo it.

  5. 5

    Stay close

    For two weeks after delivery I fix anything that comes up. Ongoing care is available separately if you want it.

Recent work

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Guides on this topic

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Frequently asked questions

What is WHMCS used for?

WHMCS handles the business side of selling online services. It takes orders, generates and emails invoices, collects payments through gateways, provisions accounts on servers, registers domains and runs a support desk. Hosting companies are its main users, but any business that bills customers on a schedule can run on it.

Why use a WHMCS specialist instead of any PHP developer?

WHMCS has its own folder rules, hook system, module conventions and payment callback flow. A developer who ignores them often edits core files, and those edits vanish at the next upgrade. A specialist already knows the supported places for custom code and the failure points around billing and cron.

Can you work on a WHMCS installation someone else built?

Yes. I start with a read-only audit of the version, PHP setup, modules, hooks and template changes, then tell you what is safe to keep and what should be rewritten. I work in a staging copy first, so the live system stays untouched while I learn how it was put together.

Do you edit WHMCS core files?

No. Core edits are overwritten on upgrade and make support from WHMCS harder. I use hooks, modules, custom template folders and language overrides instead. If a requirement truly cannot be met without touching core, I tell you that plainly before quoting, and we pick another approach.

Which WHMCS service should I start with?

Start with whatever is costing you money now. A requirement WHMCS cannot meet needs a custom module. A second system that must stay in step with billing needs an integration. A slow, aging server needs a migration. I no longer sell basic installation or one-off error fixes on their own, because an AI assistant or your host's support handles those. If you are unsure, book the free scoping call and I will tell you the order that makes sense.

How do you price WHMCS work?

I quote a fixed price after the scoping call, or work hourly at $55 to $65 per hour if the scope is open-ended. The quote lists what is included. I do not add charges for work outside it without your written agreement.

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Ready to talk about your project?

You deal with me personally from the first message to the handover. Choose the way that suits you; I reply within one business day.