Express.js Kit

Claude Code kit for Express.js framework patterns and middleware.

Features

Skills

express - Express.js framework-specific patterns

Includes patterns for:

• Clean route definitions (routes delegate to controllers)
• BaseController pattern with Sentry integration
• Middleware patterns (auth, audit with AsyncLocalStorage, error boundaries)
• Middleware ordering and composition
• Request/Response handling with TypeScript
• HTTP status codes and error handling
• Express-specific APIs and utilities

Agents

auth-route-tester - Test authenticated API routes with cookie-based auth

Specializes in:

• Testing JWT cookie-based authentication
• Verifying route functionality
• Creating test workflows
• Database record validation

auth-route-debugger - Debug authentication and route issues

Specializes in:

• 401/403 error debugging
• Cookie and JWT token issues
• Route registration problems
• Authentication flow debugging

Installation

The Express kit is automatically detected if your project has Express in package.json:

npx claude-code-setup --yes

Or install explicitly:

npx claude-code-setup --kit express,nodejs,prisma

Note: Express kit requires the nodejs kit for core backend patterns.

Auto-Activation

This skill activates when:

Keywords: backend, controller, service, route, API, endpoint, middleware, validation, Prisma, Express

Intent Patterns:

• "create a route"
• "add an endpoint"
• "implement a controller"
• "setup database access"

File Patterns:

• Editing .ts files in backend directories
• Files importing from 'express'
• Files exporting Controllers or Services

Tech Stack

• Express.js: 4.x
• TypeScript: 5+
• Prisma: ORM for database access
• Sentry: Error tracking
• Zod: Schema validation
• Node.js: 18+

Key Patterns

Controller

import { BaseController } from './BaseController';

export class PostController extends BaseController {
  constructor(private postService: PostService) {
    super();
  }

  async getPosts(req: Request, res: Response) {
    return this.handleRequest(req, res, async () => {
      const posts = await this.postService.getAllPosts();
      return { posts };
    });
  }
}

Service

export class PostService {
  constructor(private postRepository: PostRepository) {}

  async getAllPosts(): Promise<Post[]> {
    return this.postRepository.findAll();
  }
}

Route

import { Router } from 'express';

const router = Router();

router.get('/posts', postController.getPosts.bind(postController));
router.post('/posts', validate(postSchema), postController.createPost.bind(postController));

export default router;

Related Kits

• nodejs - Core Node.js backend patterns (required)
• prisma - Prisma ORM database patterns
• sentry - Sentry error tracking (coming soon)

Dependencies

This kit works best with:

• nodejs kit - Core backend architecture patterns
• prisma kit - If using Prisma for database access

Documentation

See skills/express/SKILL.md for complete documentation.