Architecture

Overview

WP Appointments is a monorepo with a WordPress plugin at its core and shared npm packages for the frontend.

PHP Backend

Namespace: WPAppointments\ with PSR-4 autoloading.

Directory	Purpose
src/Api/Endpoints/	REST controllers extending base Controller
src/Core/	Plugin bootstrap, post types, capabilities, Singleton base class
src/Data/Model/	Data models: Appointment, Customer, BookableEntity, BookableVariant
src/Data/Query/	Query classes for fetching/filtering posts
src/Bookable/	Bookable type registry and abstract handler
src/Availability/	Layered availability engine and layer registry
src/Notifications/	Email notification system
src/Utils/	Date, Schedule, Availability helpers

Custom Post Types

CPT	Slug
Appointment	wpa-appointment
Schedule	wpa-schedule
Service	wpa-service
Entity	wpa-entity

Key Patterns

• Singleton pattern — most core classes extend Core\Singleton
• Bookable Type Registry — addons register handlers via BookableTypeRegistry::register()
• Availability Layers — addons register layers via AvailabilityLayerRegistry::register()
• Capabilities — filterable: wpa_manage_appointments, wpa_manage_customers, etc.

TypeScript Frontend

Directory	Purpose
assets/backend/	React admin UI (Dashboard, Calendar, Customers, Settings)
assets/backend/store/	@wordpress/data Redux store
assets/backend/api/	API client functions using @wordpress/api-fetch
assets/frontend/	Customer-facing booking flow
assets/gutenberg/blocks/	Booking Flow Gutenberg block

State Management

Uses @wordpress/data Redux stores. Actions, reducers, selectors, and resolvers follow the WordPress data package patterns.

Form Handling

React Hook Form with Valibot schemas for validation. CSS Modules with camelCase exports.

REST API

Namespace: /wpappointments/v1/

All responses use a standardized envelope with pagination:

{
  "data": [...],
  "totalItems": 50,
  "totalPages": 5,
  "postsPerPage": 10,
  "currentPage": 1
}