modular-monolith-generator

Modular Monolith Generator

Set up (or tighten) a modular monolith: each module owns its domain, exposes a small public contract, keeps everything else internal, and talks to other modules through contracts or an in-process bus — so you get module independence without microservice overhead.

Input — point it at your project

Works on a target: a file, folder, project/solution, or GitHub URL. If modules exist, audit their boundaries; if not, propose a split. Detect with: find <target> -name "*.csproj" and grep -rn "public class\|internal class" --include=*.cs <target> | head.

Module layout

src/
├── Modules/
│   ├── Orders/
│   │   ├── Orders.Public/        # contracts other modules may use (DTOs, integration events, a façade interface)
│   │   └── Orders/               # internal: domain, handlers, EF — internal by default
│   ├── Billing/
│   │   ├── Billing.Public/
│   │   └── Billing/
├── Shared/                       # truly shared kernel only (Result, base types)
└── Host/                         # composition root: wires every module

Module registration (self-contained)

public interface IModule
{
    IServiceCollection RegisterModule(IServiceCollection services, IConfiguration config);
    void MapEndpoints(IEndpointRouteBuilder app);
}
// Host discovers and calls every IModule — no module references another module's internals.

Boundaries — enforce them, don't just hope

• A module references only other modules' .Public projects, never their internals.
• Cross-module calls go through a public façade interface or integration events on an in-process bus (MediatR notifications, or a channel) — not direct DB access into another module's tables.
• One schema per module (or clearly owned tables); no foreign keys across module boundaries.

Guardrail test (NetArchTest)

[Fact]
public void Orders_internals_are_not_referenced_by_other_modules()
{
    var result = Types.InAssembly(typeof(BillingModule).Assembly)
        .Should().NotHaveDependencyOn("Company.Modules.Orders") // internal assembly
        .GetResult();
    Assert.True(result.IsSuccessful);
}