Stack Advisor Skill

Guides users through tech stack selection via interactive Q&A for new projects where the tech stack hasn't been decided yet.

Note: For existing projects with established code, use tech-stack-detection skill instead to auto-detect installed technologies.

When to Activate

This skill activates when:

• User runs /speckit.plan without providing tech stack details
• User explicitly asks for help choosing a tech stack
• User says they "don't know" what technologies to use

Q&A Flow (3-5 Questions)

Ask these questions in order. Each answer narrows down the recommendation.

Question 1: Project Type (Required)

What type of project are you building?

1. Web Application - Interactive frontend with user interface
2. API / Backend - Server-side services, REST/GraphQL APIs
3. CLI Tool - Command-line application
4. Library / Package - Reusable code for other projects
5. Full Stack - Both frontend and backend together
6. Mobile App - iOS, Android, or cross-platform

Question 2: Project Scale (Required)

What's the expected scale of this project?

1. Prototype / Small - Quick proof of concept, personal project, learning
2. Medium - Production app, small team, moderate complexity
3. Large / Enterprise - Multiple teams, complex requirements, long-term maintenance

Question 3: Key Requirements (Required)

What are the key technical requirements? (Select all that apply)

1. Real-time updates - WebSockets, live data, collaboration
2. SEO / SSR - Search engine optimization, server-side rendering
3. Offline-first - PWA, works without internet
4. High performance - Sub-second loads, large data sets
5. Simple / Minimal - Least dependencies, vanilla approach
6. Mobile-responsive - Must work well on all devices
7. None specific - Standard requirements

Question 4: Team Preference (Optional)

What's your team's technology preference?

1. Beginner-friendly - Well-documented, large community, stable
2. Modern standards - Current best practices, good balance
3. Cutting-edge - Latest technologies, willing to accept some risk

Question 5: Constraints (Optional)

Any specific constraints or requirements?

Examples:

• "Must use Python for ML integration"
• "Company standard is .NET"
• "Avoid frameworks, keep it vanilla"
• "No constraints"

Tech Stack Decision Matrix

Web Applications

| Scale + Requirements | Recommended Stack | |---------------------|-------------------| | Prototype + Simple | Vanilla HTML/CSS/JS, or Vite + vanilla | | Prototype + Modern | Vite + React + TailwindCSS | | Medium + SEO | Next.js + React + TailwindCSS | | Medium + Real-time | Vite + React + Socket.io + TailwindCSS | | Medium + Simple | Astro (static) or SvelteKit | | Large + Enterprise | Next.js + TypeScript + TailwindCSS + Prisma | | Large + Performance | Remix or SolidStart |

API / Backend

| Scale + Requirements | Recommended Stack | |---------------------|-------------------| | Prototype | Express.js or FastAPI (Python) | | Medium + Node.js | Express + TypeScript + Prisma | | Medium + Python | FastAPI + SQLAlchemy + Pydantic | | Large + Enterprise | NestJS (Node) or Django (Python) | | High Performance | Go + Gin, or Rust + Axum |

Full Stack

| Scale + Requirements | Recommended Stack | |---------------------|-------------------| | Prototype | Next.js (full stack) or SvelteKit | | Medium | Next.js + Prisma + PostgreSQL | | Medium + Real-time | T3 Stack (Next.js + tRPC + Prisma) | | Large | Separate frontend/backend with shared types |

CLI Tools

| Language Preference | Recommended | |--------------------|-------------| | JavaScript/TypeScript | Commander.js + TypeScript | | Python | Click or Typer | | Go | Cobra | | Rust | Clap |

Libraries

| Ecosystem | Recommended Setup | |-----------|------------------| | npm (JS/TS) | TypeScript + tsup + Vitest | | PyPI (Python) | Poetry + pytest | | Crates (Rust) | Cargo (built-in) |

Standard Additions (Always Recommend)

| Category | Recommendation | |----------|---------------| | Testing | Playwright (E2E), Vitest/Jest (unit) | | Linting | ESLint + Prettier (JS/TS), Ruff (Python) | | Type Safety | TypeScript (JS), Pydantic (Python) | | Styling | TailwindCSS (unless vanilla requested) | | Version Control | Git + Conventional Commits |

Output Format

After Q&A, present the recommendation:

## Recommended Tech Stack

Based on your answers:
- **Project Type**: Web Application
- **Scale**: Medium
- **Requirements**: SEO, Mobile-responsive
- **Preference**: Modern standards

### Suggested Stack

| Category | Technology | Why |
|----------|------------|-----|
| Framework | Next.js 14 | SSR for SEO, React ecosystem |
| Language | TypeScript | Type safety, better DX |
| Styling | TailwindCSS | Rapid development, responsive utilities |
| Testing | Playwright | E2E testing, cross-browser |
| Database | PostgreSQL + Prisma | Type-safe ORM, scalable |

### Project Structure

src/ ├── app/ # Next.js App Router ├── components/ # React components ├── lib/ # Utility functions └── styles/ # Global styles

**Proceed with this stack?** (Y/n/modify)

Confirmation Flow

1. If user confirms → Proceed to plan generation with this stack
2. If user wants modifications → Ask what to change, update recommendation
3. If user says no → Ask what they'd prefer instead

Integration with /speckit.plan

When stack is confirmed, pass it to plan generation:

User confirmed stack:
- Framework: Next.js 14
- Language: TypeScript
- Styling: TailwindCSS
- Testing: Playwright

Proceeding with plan generation...

The plan template will use these values in the Tech Stack section.