Booking Clinic — Multi-Tenant Healthcare Platform

Overview​

Booking Clinic is a multi-tenant SaaS platform that lets healthcare clinics and appointment-based businesses manage their entire booking workflow. Each client (tenant) gets their own workspace with customizable branding, services, staff profiles, locations, and scheduling — all managed through a shared admin dashboard. End customers can book appointments through personalized public booking pages, with deep-link URLs that securely embed tenant and provider context.

The platform handles everything from provider schedules (recurring weekly slots) to public booking tokens, appointment confirmations, and email notifications — powered by a dedicated Rust email microservice that dispatches templated messages through AWS SES.

Key Features​

• Multi-tenant isolation: Workspace-scoped entities via BaseWorkspaceEntity, per-tenant branding, settings, and users
• Public booking with deep links: Cryptographically-secure time-limited tokens allow unauthenticated visitors to book appointments
• Advanced scheduling: Recurring weekly slots via daysOfWeek JSON, templates for standardizing provider availability
• Polyglot architecture: Node.js API for business logic, Next.js for the UI, and Rust for high-performance email dispatch — each in the right language for the job
• Fine-grained RBAC: Permissions like booking.serviceOfferingSlot.create validated through OxideAuth on every request
• Generic CRUD framework: 14 entities get full Create-Read-Update-Delete with RBAC through a single BaseModelRouter pattern

Architecture​

Booking Clinic runs as a polyglot multi-service system orchestrated via Docker Compose or Kubernetes:

• www — Next.js administrative dashboard and public booking frontend
• api — Express.js REST API with generic CRUD framework and RBAC
• email — Rust/Axum microservice for event-driven email delivery
• PostgreSQL — primary relational database for bookings and tenant data
• Redis — caching layer and pub/sub event bus for email dispatch

The API proxies all authentication through OxideAuth, CODATIVITY's centralized auth service, using service account JWTs. This keeps identity management separate from business logic.

Service-to-service flow​

Public user  →  www (booking form)  →  api (validates token, creates booking)
                                         │
                                    PostgreSQL (stores booking)
                                         │
                                    Redis pub/sub (emits event)
                                         │
                                    email (Rust) → AWS SES (sends confirmations)

Services​

www — Next.js Dashboard + Public Booking​

The frontend is a Next.js App Router application using MUI for the UI layer and FullCalendar for the scheduling interface. It serves two audiences through route groups:

• (auth) — login, registration, and auth flow pages
• (dashboard)/[tenant] — admin dashboard with Schedule (FullCalendar), Bookings, Services, Providers, Locations, Users, Templates, Settings, Workspaces, and Notifications
• (simple) — public-facing booking pages accessed via secure deep links

Key frontend features include a compile-time typed service registry using a custom useServiceSWR hook that provides type-safe API calls and automatic caching.

api — Express.js REST Backend​

The API is built on Express.js with TypeScript, using MikroORM for database access. It employs a generic BaseModelRouter pattern — 14 entity types (User, Workspace, Provider, ServiceOffering, Booking, etc.) each get automatic CRUD endpoints with RBAC enforcement.

Authentication goes through OxideAuth: the API validates incoming JWTs and enforces fine-grained permissions like booking.serviceOfferingSlot.create on every route. Storage backends are swappable between local, Azure Blob, and Hetzner S3 via configuration.

email — Rust Microservice​

A dedicated email service written in Rust using the Axum framework. It listens on Redis pub/sub channels for events (booking created, cancelled, reminder triggers) and sends formatted emails via AWS SES. Templates use Handlebars/Tera for flexible HTML generation. Has its own PostgreSQL database for email tracking and logs.

Tech Stack​