Server Applications

Build backend servers and APIs using Node.js, Python, or other frameworks. Claude Code helps you create robust server applications with databases, authentication, and more.

Overview

Server applications handle backend logic, APIs, databases, authentication, and business logic. With Claude Code, you can vibe code servers using modern frameworks and best practices.

Choose Your Stack

Node.js (JavaScript/TypeScript)

Great for JavaScript developers and real-time apps.

Popular Frameworks:

Express - Minimal and flexible
Fastify - Fast and efficient
NestJS - Enterprise-grade, TypeScript-first
Hono - Modern, ultrafast edge runtime

Python

Perfect for data-heavy apps and ML integration.

Popular Frameworks:

FastAPI - Modern, fast, with automatic docs
Django - Full-featured, batteries included
Flask - Lightweight and flexible

Go

Best for high-performance services.

Popular Frameworks:

Gin - Fast HTTP framework
Echo - High performance, minimalist
Fiber - Express-inspired

Rust

Maximum performance and safety.

Popular Frameworks:

Axum - Ergonomic and modular
Actix - Powerful and fast

Building with Node.js + Express

Setup


mkdir my-server
cd my-server
npm init -y
npm install express

Start Claude Code


claude

Example prompts


"Create an Express server with endpoints for users: GET, POST, PUT, DELETE"

"Add MongoDB connection and user schema with Mongoose"

"Implement JWT authentication with login and register endpoints"

"Add input validation using Zod"

"Create middleware for error handling and logging"

"Add rate limiting to prevent abuse"

"Implement file upload with multer"

"Add CORS configuration for my frontend at localhost:3000"

Run the server


node server.js
# or with auto-reload
npm install -D nodemon
npx nodemon server.js

Building with Python + FastAPI

Setup


mkdir my-api
cd my-api
python -m venv venv
source venv/bin/activate  # On Windows: venv\Scripts\activate
pip install fastapi uvicorn

Start Claude Code


claude

Example prompts


"Create a FastAPI server with CRUD endpoints for a todo list"

"Add SQLAlchemy database models for users and posts"

"Implement JWT authentication with OAuth2 password flow"

"Add Pydantic models for request/response validation"

"Create endpoints to upload and download files"

"Add database migrations using Alembic"

"Implement pagination for list endpoints"

"Add websocket endpoint for real-time updates"

Run the server


uvicorn main:app --reload

Common Server Features

REST API Endpoints

Create RESTful APIs:


claude "create REST endpoints for a blog: posts, comments, and users"

Database Integration

PostgreSQL


claude "connect to PostgreSQL and create a users table with email, password, and created_at"

MongoDB


claude "set up MongoDB connection and create schemas for products and orders"

SQLite


claude "use SQLite for local database with tables for tasks and categories"

Authentication & Authorization

JWT Tokens


claude "implement JWT authentication with access and refresh tokens"

Session-based Auth


claude "add session-based authentication using express-session"

OAuth2


claude "integrate Google OAuth2 login"

API Keys


claude "implement API key authentication for third-party integrations"

Validation

Validate incoming data:


claude "add validation to ensure email is valid and password is at least 8 characters"

Error Handling

Proper error responses:


claude "create centralized error handling middleware with proper HTTP status codes"

File Uploads

Handle file uploads:


claude "add endpoint to upload images with size and type validation"

Email Sending

Send transactional emails:


claude "send welcome email when user registers using Nodemailer"

Payment Processing

Integrate payments:


claude "integrate Stripe for subscription payments"

Real-time Features

WebSockets or Server-Sent Events:


claude "add WebSocket support for real-time chat"

Database ORMs

Node.js

Prisma (Recommended)


claude "set up Prisma with PostgreSQL and create user and post models"

TypeORM


claude "configure TypeORM with MySQL for an e-commerce database"

Python

SQLAlchemy


claude "create SQLAlchemy models for a blog with relationships"

Django ORM


claude "create Django models for a social media platform"

API Documentation

Auto-generated docs


claude "add Swagger/OpenAPI documentation to my Express API"

FastAPI includes automatic docs at /docs and /redoc.

Security Best Practices

Environment Variables


claude "move all secrets to environment variables using dotenv"

Rate Limiting


claude "add rate limiting: 100 requests per 15 minutes per IP"

CORS


claude "configure CORS to allow only my frontend domain"

Helmet (Node.js)


claude "add Helmet middleware for security headers"

SQL Injection Prevention


claude "ensure all database queries use parameterized statements"

Password Hashing


claude "hash passwords using bcrypt before saving to database"

Testing

Unit Tests


claude "write unit tests for the authentication functions using Jest"

Integration Tests


claude "create integration tests for all API endpoints"

API Testing


claude "write tests using Supertest to verify API responses"

Deployment

Docker


claude "create a Dockerfile to containerize my Node.js server"

Environment Variables


claude "set up environment variables for development, staging, and production"

Process Managers

PM2 (Node.js)


npm install -g pm2
pm2 start server.js

Systemd (Linux)


claude "create a systemd service file for my Python FastAPI app"

Hosting Options

Cloud Platforms

Vercel - Great for Node.js APIs (free tier)
Railway - Simple deployment (free tier available)
Render - Full-stack hosting
Fly.io - Global edge deployment
AWS - Full control, scalable
Google Cloud - Enterprise features
DigitalOcean - Simple VPS hosting

Serverless

AWS Lambda - Pay per request
Cloudflare Workers - Edge computing
Vercel Functions - Serverless functions
Netlify Functions - JAMstack serverless

Monitoring and Logging

Logging


claude "add structured logging using Winston with log rotation"

Error Tracking


claude "integrate Sentry for error tracking and monitoring"

Performance Monitoring


claude "add New Relic APM for performance monitoring"

Scaling

Caching


claude "add Redis caching for frequently accessed data"

Load Balancing


claude "configure nginx as a load balancer for my Node.js servers"

Horizontal Scaling


claude "set up my server to run multiple instances behind a load balancer"

GraphQL (Alternative to REST)


claude "convert my REST API to GraphQL using Apollo Server"

Example Projects

Blog API


claude "create a complete blog API with posts, comments, users, and authentication"

E-commerce Backend


claude "build an e-commerce API with products, cart, orders, and Stripe payments"

Chat Server


claude "create a real-time chat server with WebSockets, rooms, and message history"

File Storage Service


claude "build a file upload/download service with S3 integration"

Task Management API


claude "create a task management API with projects, tasks, and team collaboration"

Pro Tips

Always use environment variables for secrets. Never commit API keys, database passwords, or tokens to git.

Use TypeScript for better type safety and autocomplete
Implement proper error handling from the start
Add logging before deploying to production
Use a database connection pool for better performance
Implement rate limiting to prevent abuse
Always validate user input
Use HTTPS in production
Keep dependencies updated
Write tests for critical functionality
Document your API endpoints
Use database migrations for schema changes

Environment Setup

Create a .env file:


DATABASE_URL=postgresql://user:pass@localhost:5432/mydb
JWT_SECRET=your-secret-key
PORT=3000
NODE_ENV=development

Add .env to .gitignore:


echo ".env" >> .gitignore

Database Migrations


claude "set up database migrations using Prisma Migrate"

Background Jobs

For long-running tasks:


claude "implement background job processing using Bull queue and Redis"

Next Steps

Choose your framework (Express or FastAPI recommended for beginners)
Set up your project
Start Claude Code
Build your API endpoints
Add database integration
Implement authentication
Add tests
Deploy to production

Start building powerful backend services with Claude Code!