Ln 770 Crosscutting Setup

ln-770-crosscutting-setup

Type: L2 Domain Coordinator Category: 7XX Project Bootstrap Parent: ln-700-project-bootstrap

Coordinates cross-cutting concerns configuration for .NET and Python projects.

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Overview

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Phase 1: Detect Project Stack

Determine the technology stack by scanning project files.

Detection Rules:

Actions:

1. Glob for *.csproj files
2. If not found, Glob for pyproject.toml or requirements.txt
3. If Python, check for FastAPI in dependencies
4. Store detected stack in Context Store

Context Store Initial:

{
  "STACK": ".NET" | "Python",
  "FRAMEWORK": "ASP.NET Core" | "FastAPI",
  "PROJECT_ROOT": "/​path/​to/​project",
  "FRAMEWORK_VERSION": "8.0" | "0.109.0"
}

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Phase 2: Check Existing Configuration

Scan for already configured cross-cutting concerns.

Detection Patterns:

Actions:

1. Grep for each pattern
2. Mark configured concerns as skip: true
3. Update Context Store with findings

Context Store Updated:

{
  "concerns": {
    "logging": { "configured": false },
    "errorHandling": { "configured": false },
    "cors": { "configured": true, "skip": true },
    "healthChecks": { "configured": false },
    "apiDocs": { "configured": false }
  }
}

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Phase 3: Invoke Workers (Conditional)

Delegate to workers only for unconfigured concerns.

Worker Invocation Order:

Pass Context Store to each worker.

Worker Response Format:

{
  "status": "success" | "skipped" | "error",
  "files_created": ["path/​to/​file.cs"],
  "packages_added": ["Serilog.AspNetCore"],
  "message": "Configured structured logging with Serilog"
}

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Phase 4: Generate Aggregation File

Create a single entry point for all cross-cutting services.

.NET: Extensions/​ServiceExtensions.cs

Generate based on configured workers:

// Structure only - actual code generated via MCP ref
public static class ServiceExtensions
{
    public static IServiceCollection AddCrosscuttingServices(
        this IServiceCollection services,
        IConfiguration configuration)
    {
        // Calls added based on configured workers:
        // services.AddLogging(configuration);      // if ln-771 ran
        // services.AddCorsPolicy(configuration);   // if ln-773 ran
        // services.AddHealthChecks();              // if ln-774 ran
        // services.AddSwaggerServices();           // if ln-775 ran
        return services;
    }
}

Python: middleware/​__init__.py

Generate based on configured workers:

# Structure only - actual code generated via MCP ref
def configure_middleware(app):
    # Middleware added based on configured workers:
    # configure_logging(app)        # if ln-771 ran
    # configure_error_handlers(app) # if ln-772 ran
    # configure_cors(app)           # if ln-773 ran
    # configure_health_routes(app)  # if ln-774 ran
    pass

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Phase 5: Summary Report

Display summary of all configured concerns.

Output Format:

Cross-cutting Setup Complete
============================
Stack: .NET (ASP.NET Core 8.0)

Configured:
  ✓ Logging (Serilog) - Extensions/​LoggingExtensions.cs
  ✓ Error Handling - Middleware/​GlobalExceptionMiddleware.cs
  ✓ CORS - Extensions/​CorsExtensions.cs
  ✓ Health Checks - Extensions/​HealthCheckExtensions.cs
  ✓ API Docs (Swagger) - Extensions/​SwaggerExtensions.cs

Skipped (already configured):
  - None

Entry Point: Extensions/​ServiceExtensions.cs
  Add to Program.cs: builder.Services.AddCrosscuttingServices(builder.Configuration);

Packages to Install:
  dotnet add package Serilog.AspNetCore
  dotnet add package Swashbuckle.AspNetCore

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Workers

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Context Store Interface

Workers receive and return via Context Store:

Input to Workers:

{
  "STACK": ".NET",
  "FRAMEWORK": "ASP.NET Core",
  "FRAMEWORK_VERSION": "8.0",
  "PROJECT_ROOT": "/​path/​to/​project",
  "ENVIRONMENT": "Development"
}

Output from Workers:

{
  "status": "success",
  "files_created": [],
  "packages_added": [],
  "registration_code": "services.AddLogging(configuration);"
}

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Idempotency

This skill is idempotent:

• Phase 2 detects existing configuration
• Workers skip if already configured
• Aggregation file preserves existing entries

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Version: 2.0.0 Last Updated: 2026-01-10