nestjs-best-practices

Original：🇺🇸 English

Translated

2 scripts

NestJS best practices and architecture patterns for building production-ready applications. This skill should be used when writing, reviewing, or refactoring NestJS code to ensure proper patterns for modules, dependency injection, security, and performance.

1installs

Sourcemidudev/autoskills

Added on2026-05-10

NPX Install

npx skill4agent add midudev/autoskills nestjs-best-practices

SKILL.md Content

View Translation Comparison →

NestJS Best Practices

Comprehensive best practices guide for NestJS applications. Contains 40 rules across 10 categories, prioritized by impact to guide automated refactoring and code generation.

When to Apply

Reference these guidelines when:

Writing new NestJS modules, controllers, or services
Implementing authentication and authorization
Reviewing code for architecture and security issues
Refactoring existing NestJS codebases
Optimizing performance or database queries
Building microservices architectures

Rule Categories by Priority


arch-
di-
error-
security-
perf-
test-
db-
api-
micro-
devops-

Priority	Category	Impact	Prefix
1	Architecture	CRITICAL	`arch-`
2	Dependency Injection	CRITICAL	`di-`
3	Error Handling	HIGH	`error-`
4	Security	HIGH	`security-`
5	Performance	HIGH	`perf-`
6	Testing	MEDIUM-HIGH	`test-`
7	Database & ORM	MEDIUM-HIGH	`db-`
8	API Design	MEDIUM	`api-`
9	Microservices	MEDIUM	`micro-`
10	DevOps & Deployment	LOW-MEDIUM	`devops-`

Quick Reference

1. Architecture (CRITICAL)

```
arch-avoid-circular-deps
```
- Avoid circular module dependencies
```
arch-feature-modules
```
- Organize by feature, not technical layer
```
arch-module-sharing
```
- Proper module exports/imports, avoid duplicate providers
```
arch-single-responsibility
```
- Focused services over "god services"
```
arch-use-repository-pattern
```
- Abstract database logic for testability
```
arch-use-events
```
- Event-driven architecture for decoupling

2. Dependency Injection (CRITICAL)

```
di-avoid-service-locator
```
- Avoid service locator anti-pattern
```
di-interface-segregation
```
- Interface Segregation Principle (ISP)
```
di-liskov-substitution
```
- Liskov Substitution Principle (LSP)
```
di-prefer-constructor-injection
```
- Constructor over property injection
```
di-scope-awareness
```
- Understand singleton/request/transient scopes
```
di-use-interfaces-tokens
```
- Use injection tokens for interfaces

3. Error Handling (HIGH)

```
error-use-exception-filters
```
- Centralized exception handling
```
error-throw-http-exceptions
```
- Use NestJS HTTP exceptions
```
error-handle-async-errors
```
- Handle async errors properly

4. Security (HIGH)

```
security-auth-jwt
```
- Secure JWT authentication
```
security-validate-all-input
```
- Validate with class-validator
```
security-use-guards
```
- Authentication and authorization guards
```
security-sanitize-output
```
- Prevent XSS attacks
```
security-rate-limiting
```
- Implement rate limiting

5. Performance (HIGH)

```
perf-async-hooks
```
- Proper async lifecycle hooks
```
perf-use-caching
```
- Implement caching strategies
```
perf-optimize-database
```
- Optimize database queries
```
perf-lazy-loading
```
- Lazy load modules for faster startup

6. Testing (MEDIUM-HIGH)

```
test-use-testing-module
```
- Use NestJS testing utilities
```
test-e2e-supertest
```
- E2E testing with Supertest
```
test-mock-external-services
```
- Mock external dependencies

7. Database & ORM (MEDIUM-HIGH)

```
db-use-transactions
```
- Transaction management
```
db-avoid-n-plus-one
```
- Avoid N+1 query problems
```
db-use-migrations
```
- Use migrations for schema changes

8. API Design (MEDIUM)

```
api-use-dto-serialization
```
- DTO and response serialization
```
api-use-interceptors
```
- Cross-cutting concerns
```
api-versioning
```
- API versioning strategies
```
api-use-pipes
```
- Input transformation with pipes

9. Microservices (MEDIUM)

```
micro-use-patterns
```
- Message and event patterns
```
micro-use-health-checks
```
- Health checks for orchestration
```
micro-use-queues
```
- Background job processing

10. DevOps & Deployment (LOW-MEDIUM)

```
devops-use-config-module
```
- Environment configuration
```
devops-use-logging
```
- Structured logging
```
devops-graceful-shutdown
```
- Zero-downtime deployments

How to Use

Read individual rule files for detailed explanations and code examples:

rules/arch-avoid-circular-deps.md
rules/security-validate-all-input.md
rules/_sections.md

Each rule file contains:

Brief explanation of why it matters
Incorrect code example with explanation
Correct code example with explanation
Additional context and references

Full Compiled Document

For the complete guide with all rules expanded:

AGENTS.md