WordPress Plugin Development With AI

• • How WordPress plugins work: file structure, headers, and activation hooks
• • The difference between functions.php hacks and proper plugin architecture
• • Setting up your development environment: Local by Flywheel, VS Code, GitHub, and PHP debugging
• • Setting up GitHub Copilot and Claude for WordPress development
• • WordPress coding standards: naming conventions, code style, and documentation
• • Your first plugin: a working plugin that hooks into WordPress and does something real
• • Using Claude to scaffold a plugin from a plain-English description of what it should do

Exercise: Build and activate your first plugin using AI-assisted scaffolding

• • The difference between actions and filters — and when to use each
• • add_action() and add_filter(): syntax, priority, and accepted arguments
• • The most important WordPress hooks and what each one fires on
• • Hook discovery: using Query Monitor and Claude to find the right hook for any task
• • Removing and replacing other plugins' hooks
• • Building a feature using only hooks — no template overrides
• • Using AI to explain unfamiliar hooks and find the right one for your use case

Exercise: Build a plugin that modifies WordPress behaviour using at least five different hooks

• • What custom post types are and when to use them vs regular posts or pages
• • Registering a custom post type with register_post_type()
• • Labels, capabilities, supports, and rewrite arguments explained
• • Custom taxonomies: hierarchical (like categories) and non-hierarchical (like tags)
• • Meta boxes: adding custom fields to your CPT edit screen
• • Saving and retrieving custom field data securely with update_post_meta()
• • Using Claude to generate complete CPT registration code from a functional description
• • Querying CPTs with WP_Query: arguments, loops, and performance

Exercise: Register a fully functional CPT with a custom taxonomy and meta box fields

• • What the WordPress REST API is and why it matters for modern development
• • The existing REST API endpoints: posts, pages, users, media, and custom
• • Registering a custom REST API endpoint with register_rest_route()
• • Request and response objects: reading parameters and returning JSON
• • Authentication for REST API endpoints: nonces, application passwords, and JWT
• • Permissions callbacks: controlling who can access your endpoint
• • Using Claude to generate REST API endpoint code and write request validation logic
• • Testing your endpoints with Postman and the browser

Exercise: Build a custom REST API endpoint that reads and writes data for your plugin

• • When to use the WordPress Settings API vs a custom admin page
• • Registering settings with register_setting(), add_settings_section(), and add_settings_field()
• • Building a clean, standards-compliant settings page
• • Options API: get_option(), update_option(), delete_option() — and when to use each
• • Settings validation and sanitisation callbacks
• • Building a tabbed settings page for complex plugins
• • Using Claude to generate Settings API code from a list of settings requirements
• • Storing and retrieving settings data correctly for multisite compatibility

Exercise: Build a complete settings page with at least four configurable options

• • Why plugin security matters: the most common WordPress vulnerabilities are in plugins
• • Nonces: what they are, how to generate them, and how to verify them
• • Sanitisation: escaping input with sanitize_text_field(), absint(), sanitize_email(), and others
• • Escaping output: esc_html(), esc_attr(), esc_url(), esc_js() — always escape on output
• • SQL injection prevention: $wpdb->prepare() and why you must use it for custom queries
• • Capability checks: always verify the current user can do what they're trying to do
• • File inclusion vulnerabilities and how to prevent them
• • Using Claude to review plugin code for security vulnerabilities and suggest fixes

Exercise: Security audit your plugin from Sessions 1–5 and fix every identified issue

• • The WooCommerce plugin architecture and how it extends WordPress
• • WooCommerce hooks: actions and filters unique to WooCommerce
• • Adding custom fields to products: product meta boxes and variation attributes
• • Hooking into the WooCommerce checkout: adding fields, validating them, and saving data
• • Programmatically creating and modifying orders
• • WooCommerce REST API: reading and writing products, orders, and customers
• • Using Claude to navigate the WooCommerce codebase and find the right hooks

Exercise: Build a WooCommerce extension that adds a custom feature to the checkout or product page

• • Why untested plugins cause real problems and how to prevent them
• • Manual testing checklists for WordPress plugins
• • Introduction to PHPUnit for WordPress — writing your first unit test
• • Writing a plugin readme.txt: the exact format WordPress.org requires
• • Plugin headers, version numbers, and changelog best practices
• • The WordPress.org plugin submission process: what reviewers check and common rejection reasons
• • Using Claude to write plugin documentation, readme content, and inline code comments
• • Packaging your plugin for distribution: zip structure and file organisation
• • Live code review: every participant presents their plugin for group feedback
• • Course close: certificate, next steps, and the Brela developer community