Project Setup — Tech-Stack Advisor

This skill owns one thing: the kit's recommended tech-stack defaults and why. The workflows that consume it live elsewhere:

• Initializing a project / generating CLAUDE.md → dotnet-init (interactive flow, architecture questionnaire, CLAUDE.md generation)
• Assessing an existing codebase → health-check (the canonical 8-dimension graded assessment)
• EF Core schema, NuGet, or .NET version migrations → migrate
• Choosing an architecture → architecture-advisor (always ask before recommending)

Core Principles

1. Recommend a default, explain the why, let the user choose — Every dimension has a kit default, but defaults are starting points, not mandates. State the trade-off in one line so the choice is informed.
2. Prefer built-in .NET over third-party — HybridCache over Redis-client wrappers, built-in rate limiting over packages, built-in OpenAPI over Swashbuckle. Fewer dependencies means fewer licensing surprises and upgrade breaks.
3. License-aware picks — MediatR (v13+), MassTransit (v9+), and FluentAssertions (v8+) went commercial. The kit defaults to MIT alternatives: Mediator, Wolverine, plain xUnit asserts.
4. Add messaging later, not never — Most projects don't need a message bus on day one. Default to "None (add later)" and reach for Wolverine when async workflows actually appear.

Patterns

Tech-Stack Dimensions and Defaults

Dimension	Options	Default	Why
Database	PostgreSQL, SQL Server, SQLite	PostgreSQL	Open source, best EF Core provider outside SQL Server, first-class Testcontainers support
Auth	JWT Bearer, OIDC (Keycloak/Auth0), None	JWT Bearer	Simplest secure default for APIs; move to OIDC when an external IdP exists
Caching	HybridCache, Redis, None	HybridCache	Built-in, stampede protection, L1+L2 — add Redis only as its L2 backend
Messaging	Wolverine (RabbitMQ), MassTransit, None	None (add later)	Premature messaging adds ops burden; Wolverine (MIT) when needed
Observability	Serilog + OpenTelemetry, Basic logging	Serilog + OTEL	Structured logs + traces from day one are cheap; retrofitting is not
Resilience	Polly v8 pipelines, Basic retry	Polly v8	AddStandardResilienceHandler() is one line for production-grade defaults
API docs	Built-in OpenAPI + Scalar	OpenAPI + Scalar	Framework-maintained spec generation; Scalar replaces Swagger UI
Testing	xUnit v3 + Testcontainers	xUnit v3 + Testcontainers	Real databases in tests; in-memory providers hide real bugs

Once dimensions are chosen, dotnet-init bakes them into the generated CLAUDE.md, and each choice maps to a skill to load when working in that area (ef-core, authentication, caching, messaging, serilog, opentelemetry, resilience, openapi, scalar, testing).

Anti-patterns

Prescribing a Stack Without Asking

# BAD — assuming the kit defaults apply everywhere
"You should use PostgreSQL and Wolverine."
# The team runs SQL Server enterprise-wide and has zero async workflows.

# GOOD — default + trade-off + question
"Kit default is PostgreSQL (best OSS EF provider). Any organizational
constraint — existing SQL Server licenses, DBA support — that should
override it?"

Re-Running Workflows This Skill Doesn't Own

# BAD — improvising a health grading or init flow from this skill
"Let me grade your codebase across 5 categories..."
# That grading conflicts with the canonical one.

# GOOD — route to the owner
Init/CLAUDE.md → dotnet-init | Assessment → health-check | Upgrades → migrate

Decision Guide

Scenario	Route to
"Set up this project for Claude Code"	dotnet-init
"Which database/auth/caching should I use?"	This skill — table above
"How healthy is this codebase?"	health-check
"Upgrade to .NET 10" / "update packages"	migrate
"Which architecture fits?"	architecture-advisor
Stack chosen, ready to build	scaffold for the first feature