nx-workspace-architect

name: nx-workspace-architect description: Expert guidance for Nx monorepo architecture with Angular and NestJS; use when setting up new Nx workspace, creating or organizing libraries, naming conventions and tagging strategy, enforcing module boundaries, building custom generators, structuring apps vs libs, domain-driven library organization, or TypeScript path configuration.

Nx Workspace Architect

Guide for building scalable, maintainable Nx monorepos with Angular and NestJS.

Activation scope

This skill activates per-module during Stage B of the SaaS bootstrap (one roadmap item per chat session). It is NOT bundled into the Stage A foundation scaffold produced by saas-workspace-initializer. Use it when adding a new library, enforcing module boundaries on a specific module, or restructuring an existing area — not to redesign the whole workspace from scratch.

Core Principle: Libs Over Apps

• Apps: Thin shells that bootstrap and expose libraries. Minimal code.
• Libs: Where 90%+ of code lives. Organized by domain and type.

Library Type Quick Reference

Domain-Based Organization Pattern

libs/
├── [domain]/                    # e.g., user-management, inventory
│   ├── feature/                 # Angular smart components
│   ├── feature-api/             # NestJS controllers
│   ├── ui/                      # Shared UI for this domain
│   ├── data-access/             # State + API clients
│   ├── domain/                  # Domain models (if DDD)
│   └── util/                    # Domain-specific utilities
├── shared/
│   ├── ui/                      # Cross-domain UI components
│   ├── util/                    # Cross-domain utilities
│   ├── data-access/             # Cross-domain state/services
│   └── api-interfaces/          # Shared DTOs and types
└── core/
    ├── auth/                    # Authentication infrastructure
    └── config/                  # App configuration

Module Boundary Rules

Configure in .eslintrc.json:

{
  "@nx/enforce-module-boundaries": [
    "error",
    {
      "depConstraints": [
        {
          "sourceTag": "type:feature",
          "onlyDependOnLibsWithTags": ["type:feature", "type:ui", "type:data-access", "type:util", "type:api-interfaces", "type:domain"]
        },
        {
          "sourceTag": "type:ui",
          "onlyDependOnLibsWithTags": ["type:ui", "type:util", "type:api-interfaces"]
        },
        {
          "sourceTag": "type:data-access",
          "onlyDependOnLibsWithTags": ["type:data-access", "type:util", "type:api-interfaces", "type:domain"]
        },
        { "sourceTag": "type:util", "onlyDependOnLibsWithTags": ["type:util"] },
        {
          "sourceTag": "type:api-interfaces",
          "onlyDependOnLibsWithTags": ["type:api-interfaces"]
        },
        {
          "sourceTag": "scope:shared",
          "onlyDependOnLibsWithTags": ["scope:shared"]
        },
        {
          "sourceTag": "scope:*",
          "onlyDependOnLibsWithTags": ["scope:shared", "scope:*"]
        }
      ]
    }
  ]
}

Workspace Initialization Commands

# Create workspace
npx create-nx-workspace@latest my-workspace --preset=apps

# Add capabilities
npm install -D @nx/angular @nx/nest @nx/js

# Create apps
nx g @nx/angular:app web --style=scss --standalone --routing
nx g @nx/nest:app api

# Create domain library structure
nx g @nx/angular:lib feature --directory=user-management --standalone
nx g @nx/nest:lib feature-api --directory=user-management
nx g @nx/js:lib data-access --directory=user-management
nx g @nx/js:lib domain --directory=user-management
nx g @nx/angular:lib ui --directory=shared --standalone
nx g @nx/js:lib api-interfaces --directory=shared

TypeScript Path Configuration

In tsconfig.base.json:

{
  "compilerOptions": {
    "paths": {
      "@my-org/user-management/feature": ["libs/user-management/feature/src/index.ts"],
      "@my-org/user-management/data-access": ["libs/user-management/data-access/src/index.ts"],
      "@my-org/shared/ui": ["libs/shared/ui/src/index.ts"],
      "@my-org/shared/api-interfaces": ["libs/shared/api-interfaces/src/index.ts"]
    }
  }
}

Tagging Strategy

In each library's project.json:

{
  "tags": ["scope:user-management", "type:feature", "platform:angular"]
}

Tag Dimensions:

• scope: - Business domain (user-management, inventory, shared)
• type: - Library type (feature, ui, data-access, util)
• platform: - Target platform (angular, nest, shared)

Decision Matrix

References

Load these as needed for detailed guidance:

• workspace-setup.md - Full workspace initialization guide
• library-types.md - Deep dive on each library type
• library-creation.md - Step-by-step library creation
• module-boundaries.md - Boundary enforcement details
• custom-generators.md - Building Nx generators