example-backend-patterns

name	example-backend-patterns
version	1.0.0
description	TEMPLATE - Backend API development patterns. Copy and customize for your backend framework (Express, Django, Spring Boot, FastAPI, etc.)
allowed-tools	Read, Grep, Glob, WebSearch

Backend API Patterns (TEMPLATE)

This is a TEMPLATE skill. Copy this directory and customize it for your backend framework.

Quick reference for backend development patterns. For detailed examples, see linked guides.

Skill Usage

Aspect	Details
Consumer	subagent-backend-architect
Purpose	Code patterns and examples for backend implementation
Invocation	Subagents read this skill; NOT directly invocable by users
How to Customize	Replace examples below with your framework's patterns

---

Step 1: Choose Your Framework

Replace this section with your framework-specific requirements:

Option A: Express.js (Node.js)

// Example: Express with TypeScript
import { Router, Request, Response } from 'express'

const router = Router()

router.get('/api/resource', async (req: Request, res: Response) => {
  try {
    const data = await service.getData()
    res.json(data)
  } catch (error) {
    res.status(500).json({ error: error.message })
  }
})

Option B: Django (Python)

# Example: Django REST Framework
from rest_framework import viewsets
from rest_framework.response import Response

class ResourceViewSet(viewsets.ViewSet):
    def list(self, request):
        data = service.get_data()
        serializer = ResourceSerializer(data, many=True)
        return Response(serializer.data)

Option C: Spring Boot (Java)

// Example: Spring Boot REST Controller
@RestController
@RequestMapping("/api/resource")
public class ResourceController {

    @Autowired
    private ResourceService service;

    @GetMapping
    public ResponseEntity<List<Resource>> getResources() {
        List<Resource> resources = service.getAll();
        return ResponseEntity.ok(resources);
    }
}

Option D: FastAPI (Python)

# Example: FastAPI with Pydantic
from fastapi import APIRouter, Depends
from pydantic import BaseModel

router = APIRouter()

class Resource(BaseModel):
    id: int
    name: str

@router.get("/api/resource", response_model=List[Resource])
async def get_resources(service: ResourceService = Depends()):
    return await service.get_all()

---

Critical Stack Requirements (CUSTOMIZE THIS)

Feature	Your Pattern	Not Allowed
Framework	[Your backend framework]	[What to avoid]
Database	[Your database + ORM]	[What to avoid]
Validation	[Your validation library]	[What to avoid]
Auth	[Your auth approach]	[What to avoid]
Testing	[Your testing framework]	[What to avoid]

---

Quick Patterns Reference (CUSTOMIZE THIS)

Controller Pattern

[Your framework's controller/route handler example]

Service Layer Pattern

[Your service layer pattern example]

Repository/Data Access Pattern

[Your data access pattern example]

Validation Pattern

[Your validation pattern example]

Error Handling Pattern

[Your error handling pattern example]

---

Detailed Guides

When you need specific implementation details, read:

• controller-patterns.md - API endpoint patterns
• service-patterns.md - Business logic layer
• repository-patterns.md - Data access layer
• validation-patterns.md - Input validation
• auth-patterns.md - Authentication/authorization
• optimization.md - Database and API optimization

---

Common Anti-Patterns to Avoid (CUSTOMIZE THIS)

Add framework-specific anti-patterns here:

1. ❌ [Anti-pattern 1 for your framework]
2. ❌ [Anti-pattern 2 for your framework]
3. ❌ [Anti-pattern 3 for your framework]
4. ❌ N+1 database queries
5. ❌ Business logic in controllers
6. ❌ Not validating input
7. ❌ SQL injection vulnerabilities

---

Architecture Layers (CUSTOMIZE THIS)

[Your architecture pattern]

Example:
Controller → Service → Repository → Database
    ↓           ↓          ↓
  Routes    Business    Data Access
           Logic

---

Dependencies Reference (CUSTOMIZE THIS)

{
  "your-framework": "Core framework",
  "your-database-driver": "Database client",
  "your-orm": "ORM/Query builder",
  "your-validation-library": "Validation",
  "your-auth-library": "Authentication",
  "your-testing-framework": "Testing"
}

---

When to Consult This Skill

• Designing API endpoints
• Implementing business logic
• Optimizing database queries
• Adding validation
• Setting up authentication/authorization
• Implementing error handling

---

Related Skills

Skill	When to Consult
provider-resilience	Any feature that creates GitHub/Azure DevOps resources (issues, PRs, milestones, labels)
security-patterns	Authentication, authorization, input validation
api-contract-validation	Client-server model alignment

Customization Instructions

1. Copy this directory to a new skill (e.g., backend-express-patterns)
2. Update frontmatter with your skill name and description
3. Replace all examples with your framework's patterns
4. Create detailed guides in separate .md files
5. Update the architect subagent to reference this skill
6. Delete this template or move it to drafts/skills/