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.

Overview

Aspect	Details
Input	Project root directory
Output	Configured logging, error handling, CORS, health checks, API docs
Workers	ln-771 to ln-775
Stacks	.NET (ASP.NET Core), Python (FastAPI)

Phase 1: Detect Project Stack

Determine the technology stack by scanning project files.

Detection Rules:

File Pattern	Stack	Framework
`*.csproj`	.NET	ASP.NET Core
`pyproject.toml` or `requirements.txt` + FastAPI	Python	FastAPI

Actions:

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

Context Store Initial:

json

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

Phase 2: Check Existing Configuration

Scan for already configured cross-cutting concerns.

Detection Patterns:

Concern	.NET Pattern	Python Pattern
Logging	`Serilog` in *.csproj, `UseSerilog` in Program.cs	`structlog` in requirements, logging config
Error Handling	`GlobalExceptionMiddleware` , `UseExceptionHandler`	`@app.exception_handler` , exception_handlers.py
CORS	`AddCors` , `UseCors`	`CORSMiddleware`
Health Checks	`AddHealthChecks` , `MapHealthChecks`	`/health` routes
API Docs	`AddSwaggerGen` , `UseSwagger`	FastAPI auto-generates

Actions:

Grep for each pattern
Mark configured concerns as
```
skip: true
```
Update Context Store with findings

Context Store Updated:

json

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

Phase 3: Invoke Workers (Conditional)

Delegate to workers only for unconfigured concerns.

Worker Invocation Order:


/skill ln-771-logging-configurator
/skill ln-772-error-handler-setup
/skill ln-773-cors-configurator
/skill ln-774-healthcheck-setup
/skill ln-775-api-docs-generator

Order	Worker	Condition	Skill Call
1	ln-771-logging-configurator	`logging.configured == false`	`/skill ln-771-logging-configurator`
2	ln-772-error-handler-setup	`errorHandling.configured == false`	`/skill ln-772-error-handler-setup`
3	ln-773-cors-configurator	`cors.configured == false`	`/skill ln-773-cors-configurator`
4	ln-774-healthcheck-setup	`healthChecks.configured == false`	`/skill ln-774-healthcheck-setup`
5	ln-775-api-docs-generator	`apiDocs.configured == false`	`/skill ln-775-api-docs-generator`

Pass Context Store to each worker.

Worker Response Format:

json

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

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

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

Workers

Worker	Purpose	Stacks
ln-771-logging-configurator	Structured logging	.NET (Serilog), Python (structlog)
ln-772-error-handler-setup	Global exception middleware	.NET, Python
ln-773-cors-configurator	CORS policy configuration	.NET, Python
ln-774-healthcheck-setup	/health endpoints	.NET, Python
ln-775-api-docs-generator	Swagger/OpenAPI	.NET (Swashbuckle), Python (FastAPI built-in)

Context Store Interface

Workers receive and return via Context Store:

Input to Workers:

json

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

Output from Workers:

json

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

Idempotency

This skill is idempotent:

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

Version: 2.0.0 Last Updated: 2026-01-10

ln-770-crosscutting-setup

NPX Install

Tags

SKILL.md Content

ln-770-crosscutting-setup

Overview

Phase 1: Detect Project Stack

Phase 2: Check Existing Configuration

Phase 3: Invoke Workers (Conditional)

Phase 4: Generate Aggregation File

.NET: Extensions/ServiceExtensions.cs

Python: middleware/init.py

Phase 5: Summary Report

Workers

Context Store Interface

Idempotency