modulus add-module

Adds a new feature module to an existing Modulus solution. Each module is generated with a full five-layer architecture and three test projects, following clean architecture principles with enforced boundaries.

Synopsis

modulus add-module <module-name> [options]

Arguments

Argument	Description
<module-name>	PascalCase name for the module (e.g., Catalog, OrderManagement).

Options

Option	Description	Default
--solution, -s <path>	Path to the .slnx solution file. If omitted, the CLI auto-discovers the nearest solution by walking up the directory tree.	Auto-discovered
--no-endpoints	Skip generating the Api layer project. Useful for modules that only communicate via integration events and have no HTTP surface.	Api layer included

Generated Output

Running modulus add-module Catalog inside an EShop solution generates:

src/
└── Modules/
    └── Catalog/
        ├── EShop.Modules.Catalog.Domain/
        │   ├── EShop.Modules.Catalog.Domain.csproj
        │   └── Entities/
        ├── EShop.Modules.Catalog.Application/
        │   ├── EShop.Modules.Catalog.Application.csproj
        │   ├── Commands/
        │   ├── Queries/
        │   └── Contracts/
        ├── EShop.Modules.Catalog.Infrastructure/
        │   ├── EShop.Modules.Catalog.Infrastructure.csproj
        │   ├── Persistence/
        │   │   └── CatalogDbContext.cs
        │   └── CatalogModuleInstaller.cs
        ├── EShop.Modules.Catalog.Api/
        │   ├── EShop.Modules.Catalog.Api.csproj
        │   ├── Endpoints/
        │   └── CatalogModule.cs
        └── EShop.Modules.Catalog.Integration/
            ├── EShop.Modules.Catalog.Integration.csproj
            └── Events/

tests/
└── Modules/
    └── Catalog/
        ├── EShop.Modules.Catalog.UnitTests/
        │   └── EShop.Modules.Catalog.UnitTests.csproj
        ├── EShop.Modules.Catalog.IntegrationTests/
        │   └── EShop.Modules.Catalog.IntegrationTests.csproj
        └── EShop.Modules.Catalog.ArchitectureTests/
            ├── EShop.Modules.Catalog.ArchitectureTests.csproj
            └── LayerDependencyTests.cs

Layer Responsibilities

Layer	Purpose
Domain	Entities, aggregate roots, value objects, domain events, repository interfaces
Application	Commands, queries, handlers, validators, DTOs, application contracts
Infrastructure	EF Core DbContext, repository implementations, external service integrations
Api	Minimal API endpoint definitions and module route registration
Integration	Integration events shared with other modules via the message bus

Automatic Updates

When you add a module, the CLI also:

1. Updates the solution file (EShop.slnx) -- All five source projects and three test projects are added to the solution with proper folder grouping.
2. Updates ModuleRegistration.cs -- The module's installer is registered in the WebApi composition root so it is discovered at startup.

Examples

Add a module with all five layers:

modulus add-module Catalog

Add a module without the Api layer (backend-only module):

modulus add-module Notifications --no-endpoints

Add a module to a specific solution:

modulus add-module Billing --solution ./path/to/EShop.slnx

See Also

• modulus init -- Create the solution first
• modulus list-modules -- See all modules in the solution
• modulus add-entity -- Add entities to your new module
• Module Anatomy -- Deep dive into the five-layer structure