Developer Resources

Resources for developers including how-to guides, api documentation and code samples.

Modules

Extend WHMCS functionality by creating a module.

Create a module
Code Samples (Github)

Hooks

Tie into events as they occur inside WHMCS.

Hooks Overview
Hook Directory

API

Interact with WHMCS from custom code & third party applications.

API Overview Sample Code Function Directory Internal API

Templates

Design and develop custom themes.

Customising WHMCS Template Language/Syntax Reference Client Area Admin Area Order Forms PDF Invoice

OAuth/OpenID

APIs for Authenticating with WHMCS

WHMCS Single Sign-On OpenID Connect

Reference Docs

The following articles are available for reference.

Internal Functions Interacting with the Database Creating Your Own Pages Language Files

App Store

Find out How it Works and How to Submit a Listing.