This is a scalable backend application for user authentication and event logging. Designed with a modular structure for maintainability and growth. Built with Fastify, Kafka, TypeScript, and Zod — it integrates PostgreSQL, DynamoDB, and ClickHouse to handle user management, events, and enable powerful analytics. Ideal for modern, event-driven systems that require observability, traceability, and flexibility.

• Backend: Fastify, TypeScript
• Event Streaming: Kafka
• Database: PostgreSQL, ClickHouse, DynamoDB
• Authentication: JWT + Bcrypt
• Kafka Client: kafkajs
• Validation: Zod

• ✅ User registration
• ✅ Login with JWT token generation
• ✅ Event-driven architecture with Kafka
• ✅ Event logs stored in:
  • PostgreSQL for relational data
  • ClickHouse for analytics
  • DynamoDB for fast key-based access
• ✅ TypeScript with Zod validation and password hashing
• ✅ Custom metadata logging: IP address, user agent, service, environment, etc.
• ✅ Environment-based configuration

.
├── docker/                   # Docker config and inits
├── prisma/                   # Prisma models and migrations
├── src/
│   ├── config/               # Environment configs
│   ├── consumers/            # Kafka consumers
│   ├── controllers/          # Route handlers (e.g. auth)
│   ├── middlewares/          # Middlewares (e.g. auth)
│   ├── services/             # Business logic (users, logs, events, consumer)
│   ├── routes/               # Route definitions
│   ├── models/               # Structure definitions and schemas
│   ├── utils/                # Utilities (e.g. JWT, logger)
│   ├── types/                # All Zod schemas
│   └── index.ts              # Main Fastify server
├── .env                      # Environment variables
└── README.md
└── docker-compose.yaml

git clone https://github.com/your-username/fastify-events-stream.git
cd fastify-events-stream

Create a .env file with required variables, you can check the example.env.

docker compose up -d

npm install
npm run build

npm run generate-db
npm run create-dDb-table

npm run start

npm run consumer-up

Registers a new user and emits a Kafka event.

{
  "username": "john_doe",
  "email": "[email protected]",
  "password": "StrongPass123!"
}

Returns a JWT token on successful login.

{
  "username": "john_doe",
  "password": "StrongPass123!"
}

Create custom events (auth Bearer is require)

{
    "serviceName": "user_test"
}

Returns information about events. All routes are protected by the auth middleware, so a valid Bearer token is required.

• api/v1/auth/me - Get information about me
• api/v1/events/:eventId - Get information about a event
• api/v1/events/recent?topEvents=5 - Get the top # of events
• api/v1/analytics/top-events - Get the top 10 events information
• api/v1/analytics/user/:userId - Get the events by userId

Each action emits a Kafka event with rich metadata:

{
  id: 'uuid',
  event_type: 'analytics_user',
  user_id: "uuid",
  action_type: "events",
  metadata: {
    ip_address: "192.168.1.1",
    user_agent: "Mozilla/5.0",
    resource_type: "auth",
    timestamp: "2025-04-13T12:34:56Z",
    result: "success",
    service_name: "auth-service",
    environment: "dev",
    version: "1.0.0"
  }
}

• Event-driven logging decouples user actions from analytics or audit systems.
• Typed contracts ensure strong consistency across producers and consumers.
• Zod provides centralized and type-safe input validation.
• JWT-based auth allows for stateless, scalable session handling.
• Kafka consumers are grouped by domain (auth, analytics, etc.) to ensure independence.

You can use Postman or any HTTP client to test endpoints. Kafka events can be observed via Kafka UI or logs. Logs are persisted in PostgreSQL and ClickHouse.

• Add unit/integration tests
• Add refresh token logic
• [✅] Handle the already exist error in the consumer
• [✅] Add OpenAPI (Swagger) docs
• [✅] Make modular the consumer
• [✅] Create docker for run the API
• [✅] Create docker for run the consumer

MIT

Feel free to open issues or submit pull requests to improve the project.