Backend Development

Backend Development

API Design

RESTful Conventions

GET    /users          # List users
POST   /users          # Create user
GET    /users/:id      # Get user
PUT    /users/:id      # Update user (full)
PATCH  /users/:id      # Update user (partial)
DELETE /users/:id      # Delete user

GET    /users/:id/posts  # List user's posts
POST   /users/:id/posts  # Create post for user

Response Format

{
  "data": { ... },
  "meta": {
    "page": 1,
    "per_page": 20,
    "total": 100
  }
}

Error Format

{
  "error": {
    "code": "VALIDATION_ERROR",
    "message": "Invalid input",
    "details": [
      { "field": "email", "message": "Invalid format" }
    ]
  }
}

Database Patterns

Schema Design

-- Use UUIDs for public IDs
CREATE TABLE users (
  id SERIAL PRIMARY KEY,
  public_id UUID DEFAULT gen_random_uuid() UNIQUE,
  email VARCHAR(255) UNIQUE NOT NULL,
  created_at TIMESTAMPTZ DEFAULT NOW(),
  updated_at TIMESTAMPTZ DEFAULT NOW()
);

-- Soft deletes
ALTER TABLE users ADD COLUMN deleted_at TIMESTAMPTZ;

-- Indexes
CREATE INDEX idx_users_email ON users(email);
CREATE INDEX idx_users_created ON users(created_at DESC);

Query Patterns

-- Pagination with cursor
SELECT * FROM posts
WHERE created_at  {
  const cached = await redis.get(`user:${id}`);
  if (cached) return JSON.parse(cached);

  const user = await db.users.findById(id);
  await redis.setex(`user:${id}`, 3600, JSON.stringify(user));
  return user;
}

// Cache invalidation
async function updateUser(id: string, data: Partial) {
  await db.users.update(id, data);
  await redis.del(`user:${id}`);
}

Rate Limiting

const limiter = rateLimit({
  windowMs: 60 * 1000,  // 1 minute
  max: 100,             // 100 requests per window
  keyGenerator: (req) => req.ip,
  handler: (req, res) => {
    res.status(429).json({ error: 'Too many requests' });
  }
});

Observability

• Logging: Structured JSON logs with request IDs
• Metrics: Request latency, error rates, queue depths
• Tracing: Distributed tracing with correlation IDs
• Health checks: /health and /ready endpoints

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: MoizIbnYousaf
• Source: MoizIbnYousaf/Ai-Agent-Skills
• License: MIT
• Homepage: https://github.com/MoizIbnYousaf/Ai-Agent-Skills#readme

Install and usage instructions live in the source repository linked above.