Nestjs Patterns
NestJS is a progressive Node.js framework built with TypeScript, designed for building scalable server-side applications using architectural patterns from Angular, including Dependency Injection, Modu
Best use case
Nestjs Patterns is best used when you need a repeatable AI agent workflow instead of a one-off prompt.
NestJS is a progressive Node.js framework built with TypeScript, designed for building scalable server-side applications using architectural patterns from Angular, including Dependency Injection, Modu
Teams using Nestjs Patterns should expect a more consistent output, faster repeated execution, less prompt rewriting.
When to use this skill
- You want a reusable workflow that can be run more than once with consistent structure.
When not to use this skill
- You only need a quick one-off answer and do not need a reusable workflow.
- You cannot install or maintain the underlying files, dependencies, or repository context.
Installation
Claude Code / Cursor / Codex
Manual Installation
- Download SKILL.md from GitHub
- Place it in
.claude/skills/nestjs-patterns/SKILL.mdinside your project - Restart your AI agent — it will auto-discover the skill
How Nestjs Patterns Compares
| Feature / Agent | Nestjs Patterns | Standard Approach |
|---|---|---|
| Platform Support | Not specified | Limited / Varies |
| Context Awareness | High | Baseline |
| Installation Complexity | Unknown | N/A |
Frequently Asked Questions
What does this skill do?
NestJS is a progressive Node.js framework built with TypeScript, designed for building scalable server-side applications using architectural patterns from Angular, including Dependency Injection, Modu
Where can I find the source code?
You can find the source code on GitHub using the link provided at the top of the page.
SKILL.md Source
# Nestjs Patterns
## Skill Profile
*(Select at least one profile to enable specific modules)*
- [ ] **DevOps**
- [x] **Backend**
- [ ] **Frontend**
- [ ] **AI-RAG**
- [ ] **Security Critical**
## Overview
NestJS is a progressive Node.js framework built with TypeScript, designed for building scalable server-side applications using architectural patterns from Angular, including Dependency Injection, Modules, and Decorators.
NestJS consists of:
- **Modular Architecture**: Module-based organization for scalable applications
- **Dependency Injection**: Built-in DI system for testable code
- **Decorators**: TypeScript decorators for clean code
- **TypeScript Support**: First-class TypeScript support
- **Enterprise Ready**: Built-in patterns for microservices, GraphQL, WebSocket
- **Testability**: DI system makes unit testing straightforward
## Why This Matters
- **Scalability**: Modular architecture makes managing large codebases easier
- **Type Safety**: Built-in TypeScript support reduces runtime errors
- **Enterprise Ready**: Built-in patterns for microservices, GraphQL, WebSocket
- **Testability**: DI system makes unit testing straightforward
---
## Core Concepts & Rules
### 1. Core Principles
- Follow established patterns and conventions
- Maintain consistency across codebase
- Document decisions and trade-offs
### 2. Implementation Guidelines
- Start with the simplest viable solution
- Iterate based on feedback and requirements
- Test thoroughly before deployment
## Inputs / Outputs / Contracts
* **Inputs**:
- Application requirements
- Module requirements
- Controller requirements
- Provider requirements
* **Entry Conditions**:
- Node.js 16+ is available
- NestJS is installed
- TypeScript is configured
- Application design is defined
* **Outputs**:
- NestJS modules
- Controllers
- Services
- Providers
* **Artifacts Required (Deliverables)**:
- Module definitions
- Controller implementations
- Service implementations
- DTOs
- Exception filters
* **Acceptance Evidence**:
- Modules work correctly
- Controllers handle requests
- Services implement business logic
- Exception handling works
* **Success Criteria**:
- Application is modular
- DI works correctly
- Controllers are clean
- Exception handling is consistent
## Skill Composition
* **Depends on**: [typescript-standards](../../01-foundations/typescript-standards/SKILL.md), [error-handling](../error-handling/SKILL.md)
* **Compatible with**: [express-rest](../express-rest/SKILL.md), [fastapi-patterns](../fastapi-patterns/SKILL.md)
* **Conflicts with**: None
* **Related Skills**: [api-design](../../01-foundations/api-design/SKILL.md), [monitoring-observability](../../14-monitoring-observability/SKILL.md)
---
## Quick Start / Implementation Example
1. Review requirements and constraints
2. Set up development environment
3. Implement core functionality following patterns
4. Write tests for critical paths
5. Run tests and fix issues
6. Document any deviations or decisions
```python
# Example implementation following best practices
def example_function():
# Your implementation here
pass
```
## Assumptions / Constraints / Non-goals
* **Assumptions**:
- Development environment is properly configured
- Required dependencies are available
- Team has basic understanding of domain
* **Constraints**:
- Must follow existing codebase conventions
- Time and resource limitations
- Compatibility requirements
* **Non-goals**:
- This skill does not cover edge cases outside scope
- Not a replacement for formal training
## Compatibility & Prerequisites
* **Supported Versions**:
- Python 3.8+
- Node.js 16+
- Modern browsers (Chrome, Firefox, Safari, Edge)
* **Required AI Tools**:
- Code editor (VS Code recommended)
- Testing framework appropriate for language
- Version control (Git)
* **Dependencies**:
- Language-specific package manager
- Build tools
- Testing libraries
* **Environment Setup**:
- `.env.example` keys: `API_KEY`, `DATABASE_URL` (no values)
## Test Scenario Matrix (QA Strategy)
| Type | Focus Area | Required Scenarios / Mocks |
| :--- | :--- | :--- |
| **Unit** | Core Logic | Must cover primary logic and at least 3 edge/error cases. Target minimum 80% coverage |
| **Integration** | DB / API | All external API calls or database connections must be mocked during unit tests |
| **E2E** | User Journey | Critical user flows to test |
| **Performance** | Latency / Load | Benchmark requirements |
| **Security** | Vuln / Auth | SAST/DAST or dependency audit |
| **Frontend** | UX / A11y | Accessibility checklist (WCAG), Performance Budget (Lighthouse score) |
## Technical Guardrails & Security Threat Model
### 1. Security & Privacy (Threat Model)
* **Top Threats**: Injection attacks, authentication bypass, data exposure
- [ ] **Data Handling**: Sanitize all user inputs to prevent Injection attacks. Never log raw PII
- [ ] **Secrets Management**: No hardcoded API keys. Use Env Vars/Secrets Manager
- [ ] **Authorization**: Validate user permissions before state changes
### 2. Performance & Resources
- [ ] **Execution Efficiency**: Consider time complexity for algorithms
- [ ] **Memory Management**: Use streams/pagination for large data
- [ ] **Resource Cleanup**: Close DB connections/file handlers in finally blocks
### 3. Architecture & Scalability
- [ ] **Design Pattern**: Follow SOLID principles, use Dependency Injection
- [ ] **Modularity**: Decouple logic from UI/Frameworks
### 4. Observability & Reliability
- [ ] **Logging Standards**: Structured JSON, include trace IDs `request_id`
- [ ] **Metrics**: Track `error_rate`, `latency`, `queue_depth`
- [ ] **Error Handling**: Standardized error codes, no bare except
- [ ] **Observability Artifacts**:
- **Log Fields**: timestamp, level, message, request_id
- **Metrics**: request_count, error_count, response_time
- **Dashboards/Alerts**: High Error Rate > 5%
## Agent Directives & Error Recovery
*(ข้อกำหนดสำหรับ AI Agent ในการคิดและแก้ปัญหาเมื่อเกิดข้อผิดพลาด)*
- **Thinking Process**: Analyze root cause before fixing. Do not brute-force.
- **Fallback Strategy**: Stop after 3 failed test attempts. Output root cause and ask for human intervention/clarification.
- **Self-Review**: Check against Guardrails & Anti-patterns before finalizing.
- **Output Constraints**: Output ONLY the modified code block. Do not explain unless asked.
## Definition of Done (DoD) Checklist
- [ ] Tests passed + coverage met
- [ ] Lint/Typecheck passed
- [ ] Logging/Metrics/Trace implemented
- [ ] Security checks passed
- [ ] Documentation/Changelog updated
- [ ] Accessibility/Performance requirements met (if frontend)
## Anti-patterns / Pitfalls
* ⛔ **Don't**: Log PII, catch-all exception, N+1 queries
* ⚠️ **Watch out for**: Common symptoms and quick fixes
* 💡 **Instead**: Use proper error handling, pagination, and logging
## Reference Links & Examples
* Internal documentation and examples
* Official documentation and best practices
* Community resources and discussions
## Versioning & Changelog
* **Version**: 1.0.0
* **Changelog**:
- 2026-02-22: Initial version with complete template structureRelated Skills
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