Build production-ready Node.js backend services with Express/Fastify, implementing middleware patterns, error handling, authentication, database integration, and API design best practices.
SkillScore82Maintained
Automatic
◆Coding pack
Last verified 8/7/2026
What it changes
Passed 18 of 22 test cases with the skill, and 9 of 22 without it.
Without skill41%
With skill82%
Checks it passed that the model alone missed
Written in TypeScript.
Implements the route handler using TypeScript.
Written in TypeScript with explicit type annotations.
9 fixed9 passed either way4 still failing0 broke
Pass-rate lift
+41 pp
Tokens
+17%
Agent turns
0%
Response time
+2%
Model gemini-3.6-flashMeasured 8/7/2026v118 of 22 cases passed with skill
Tokens, turns and time describe resource use, not a dollar price.
See it in action
One of 9 test cases the skill fixed. Same model, same prompt, with and without the skill.
1 of 9
Prompt
Can you design a foundational middleware setup for my Node.js REST API? Please supply the code for validating request payloads, configuring security headers and CORS, and adding request rate limiting before routes are processed.
What was checked, without and with the skill
Checked
Without skill
With skill
Written in TypeScript with explicit type annotations.
Missed
Passed
Avoids using wildcard origins for CORS configuration.
Passed
Passed
Integrates a schema validation library such as Zod or Joi for request payload checking.
Passed
Passed
case-02 · gemini-3.6-flash · 8/7/2026 · answers are capped and redacted
What's inside
The instructions your model reads when the skill loads.
SKILL.md40 lines3 files
Node.js Backend Patterns
Comprehensive guidance for building scalable, maintainable, and production-ready Node.js backend applications with modern frameworks, architectural patterns, and best practices.
When to Use This Skill
Building REST APIs or GraphQL servers
Creating microservices with Node.js
Implementing authentication and authorization
Designing scalable backend architectures
Setting up middleware and error handling
Integrating databases (SQL and NoSQL)
Building real-time applications with WebSockets
Implementing background job processing
Detailed patterns and worked examples
Detailed pattern documentation lives in references/details.md. Read that file when the navigation tier above is insufficient.
Best Practices
Use TypeScript: Type safety prevents runtime errors
Implement proper error handling: Use custom error classes
Validate input: Use libraries like Zod or Joi
Use environment variables: Never hardcode secrets
Implement logging: Use structured logging (Pino, Winston)
Add rate limiting: Prevent abuse
Use HTTPS: Always in production
Implement CORS properly: Don't use * in production
Use dependency injection: Easier testing and maintenance
Write tests: Unit, integration, and E2E tests
Handle graceful shutdown: Clean up resources
Use connection pooling: For databases
Implement health checks: For monitoring
Use compression: Reduce response size
Monitor performance: Use APM tools
Testing Patterns
See javascript-testing-patterns skill for comprehensive testing guidance.