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.