Effect API Example

A monorepo example demonstrating how to build a type-safe API using Effect, @effect/platform, and Drizzle ORM.

Repository Structure

effect-api-example/
├── apps/
│   └── server/                 # Bun HTTP server
│       ├── src/
│       │   ├── api/
│       │   │   ├── groups/     # API endpoint handlers
│       │   │   └── middleware/ # Auth middleware implementations
│       │   ├── db/
│       │   │   ├── schema/     # Drizzle table schemas
│       │   │   ├── migrations/ # Database migrations
│       │   │   └── SqlLive.ts  # Database layer
│       │   └── main.ts         # Server entrypoint
│       ├── scripts/
│       │   ├── seed.ts         # Database seeding script
│       │   └── client-example.ts # Example API client
│       ├── docker-compose.yml  # PostgreSQL container
│       └── drizzle.config.ts   # Drizzle Kit configuration
├── packages/
│   ├── api/                    # API definition (schemas, endpoints, middleware)
│   │   └── src/definition/
│   │       ├── groups/         # Endpoint group definitions
│   │       ├── middleware/     # Middleware definitions
│   │       └── WarpApi.ts      # Main API definition
│   ├── shared/                 # Shared types and utilities
│   │   └── src/index.ts        # Branded types, schemas, helpers
│   ├── eslint-config/          # Shared ESLint configuration
│   └── typescript-config/      # Shared TypeScript configuration

Prerequisites

• Node.js (v20+)
• pnpm (v9+)
• Bun (for running the server)
• Docker (for PostgreSQL)

Installation

# Clone the repository
git clone <repo-url>
cd effect-api-example

# Install dependencies
pnpm install

Running the Project

1. Start the Database

cd apps/server
docker compose up -d

This starts a PostgreSQL container with:

• Host: localhost
• Port: 5432
• Database: postgres
• User: postgres
• Password: postgres_password

2. Configure Environment

Copy the example environment file:

cd apps/server
cp .env.example .env

The .env file should contain:

DB_HOST=localhost
DB_PORT=5432
DB_NAME=postgres
DB_USERNAME=postgres
DB_PASSWORD=postgres_password

3. Run Database Migrations

pnpm --filter @effect-api-example/server db:migrate

4. Seed the Database (Optional)

Populate the database with 1000 sample employees:

pnpm --filter @effect-api-example/server db:seed

5. Start the Server

pnpm --filter @effect-api-example/server dev

The server runs on http://localhost:9277 by default.

6. Test the API (Optional)

Run the example client to test the API:

pnpm --filter @effect-api-example/server client:example

Available Scripts

Root

Script	Description
pnpm build	Build all packages
pnpm dev	Start development mode for all packages
pnpm lint	Lint all packages
pnpm format	Format code with Prettier

Server (apps/server)

Script	Description
pnpm dev	Start server in hot-reload mode
pnpm build	Build server for production
pnpm start	Run production build
pnpm db:generate	Generate new migrations
pnpm db:migrate	Apply migrations
pnpm db:seed	Seed database with sample data
pnpm client:example	Run example API client

API Endpoints

Health

• GET /health - Health check endpoint

Employees

All employee endpoints require an x-api-key header.

• GET /employees - List employees with pagination
  • Query params: limit, afterId, beforeId, types[]
• GET /employees/:id - Get employee by tag

Tech Stack

• Runtime: Bun
• Framework: @effect/platform HTTP API
• Database: PostgreSQL with Drizzle ORM
• Type Safety: Effect Schema
• Monorepo: Turborepo with pnpm workspaces