api_bun - Multi-tenant SaaS API Boilerplate

A professional, scalable, and modular SaaS API boilerplate built with Bun.js, ElysiaJS, and Mongoose.

🚀 Technologies

• Runtime: Bun.js (Latest)
• Framework: ElysiaJS
• ORM: Mongoose (MongoDB)
• Auth: BetterAuth with JWT
• Documentation: Swagger
• Validation: Zod (via Elysia TypeBox/t)
• Payments: Stripe
• Email: Nodemailer
• Architecture: Clean Architecture, SOLID, Repository Pattern

📂 Project Structure

src/
├── application/      # Use Cases & DTOs (Business Logic)
├── core/             # Global Config, Errors, Logger
├── domain/           # Entities & Repository Interfaces (Enterprise Rules)
├── infrastructure/   # DB, Repositories Impl, External Services (Stripe, Email)
├── presentation/     # Controllers, Routes, Middlewares
├── shared/           # Utils & Constants
└── tests/            # Automated Tests

🛠️ Installation

1. Install Bun:

   curl -fsSL https://bun.sh/install | bash

2. Install Dependencies:

   bun install

3. Environment Variables: Fill in your credentials in the .env file.

4. Run Development Server:

   bun run src/index.ts

5. Run Tests:

   bun test

📖 API Documentation

Once the server is running, access the Swagger documentation at: http://localhost:3000/doc

🔑 Key Features

• Multi-tenancy: Built-in structure for tenant isolation.
• Clean Architecture: Decoupled layers for easy maintenance and database swapping.
• Error Handling: Global middleware with custom API error classes.
• Logging: Native Bun logging to files in /logs.
• SaaS Workflow: User registration -> Email verification -> Subscription -> Admin privileges.

📜 Business Rules

• Roles: ADMIN, OWNER, MANAGER, USER.
• Registration: Users start as inactive with USER role.
• Verification: Account activation via email code.
• Upgrading: Upon subscription, users are promoted to ADMIN (Tenant Owner) to manage their own users.