---
name: tech-stack-evaluator
description: Use when comparing technology stacks, evaluating frameworks/providers, or assessing TCO, security, and ecosystem health for migration decisions.
---

# Technology Stack Evaluator

Evaluate and compare technologies, frameworks, and cloud providers with data-driven analysis and actionable recommendations.

## When to Use
- You need to compare frameworks, cloud providers, or technology stacks across cost, ecosystem, security, or migration criteria.
- You are preparing a migration recommendation or technology selection spreadsheet with TCO and risk factors.
- The decision requires structured scoring (ecosystem health, security, performance).

## When NOT to Use
- The request is for a quick coding question or implementation detail unrelated to evaluating tech stacks.
- The situation involves a single technology with no comparison or migration decision.
- You only need a high-level opinion without structured analysis or evidence.

## Table of Contents

- [Capabilities](#capabilities)
- [Quick Start](#quick-start)
- [Input Formats](#input-formats)
- [Analysis Types](#analysis-types)
- [Scripts](#scripts)
- [References](#references)

---

## Capabilities

| Capability | Description |
|------------|-------------|
| Technology Comparison | Compare frameworks and libraries with weighted scoring |
| TCO Analysis | Calculate 5-year total cost including hidden costs |
| Ecosystem Health | Assess GitHub metrics, npm adoption, community strength |
| Security Assessment | Evaluate vulnerabilities and compliance readiness |
| Migration Analysis | Estimate effort, risks, and timeline for migrations |
| Cloud Comparison | Compare AWS, Azure, GCP for specific workloads |

---

## Quick Start

### Compare Two Technologies

```
Compare React vs Vue for a SaaS dashboard.
Priorities: developer productivity (40%), ecosystem (30%), performance (30%).
```

### Calculate TCO

```
Calculate 5-year TCO for Next.js on Vercel.
Team: 8 developers. Hosting: $2500/month. Growth: 40%/year.
```

### Assess Migration

```
Evaluate migrating from Angular.js to React.
Codebase: 50,000 lines, 200 components. Team: 6 developers.
```

---

## Input Formats

The evaluator accepts three input formats:

**Text** - Natural language queries
```
Compare PostgreSQL vs MongoDB for our e-commerce platform.
```

**YAML** - Structured input for automation
```yaml
comparison:
  technologies: ["React", "Vue"]
  use_case: "SaaS dashboard"
  weights:
    ecosystem: 30
    performance: 25
    developer_experience: 45
```

**JSON** - Programmatic integration
```json
{
  "technologies": ["React", "Vue"],
  "use_case": "SaaS dashboard"
}
```

---

## Analysis Types

### Quick Comparison (200-300 tokens)
- Weighted scores and recommendation
- Top 3 decision factors
- Confidence level

### Standard Analysis (500-800 tokens)
- Comparison matrix
- TCO overview
- Security summary

### Full Report (1200-1500 tokens)
- All metrics and calculations
- Migration analysis
- Detailed recommendations

---

## Scripts

### stack_comparator.py

Compare technologies with customizable weighted criteria.

```bash
python scripts/stack_comparator.py --help
```

### tco_calculator.py

Calculate total cost of ownership over multi-year projections.

```bash
python scripts/tco_calculator.py --input assets/sample_input_tco.json
```

### ecosystem_analyzer.py

Analyze ecosystem health from GitHub, npm, and community metrics.

```bash
python scripts/ecosystem_analyzer.py --technology react
```

### security_assessor.py

Evaluate security posture and compliance readiness.

```bash
python scripts/security_assessor.py --technology express --compliance soc2,gdpr
```

### migration_analyzer.py

Estimate migration complexity, effort, and risks.

```bash
python scripts/migration_analyzer.py --from angular-1.x --to react
```

---

## References

| Document | Content |
|----------|---------|
| `references/metrics.md` | Detailed scoring algorithms and calculation formulas |
| `references/examples.md` | Input/output examples for all analysis types |
| `references/workflows.md` | Step-by-step evaluation workflows |

---

## Confidence Levels

| Level | Score | Interpretation |
|-------|-------|----------------|
| High | 80-100% | Clear winner, strong data |
| Medium | 50-79% | Trade-offs present, moderate uncertainty |
| Low | < 50% | Close call, limited data |

---

## When to Use

- Comparing frontend/backend frameworks for new projects
- Evaluating cloud providers for specific workloads
- Planning technology migrations with risk assessment
- Calculating build vs. buy decisions with TCO
- Assessing open-source library viability

## When NOT to Use

- Trivial decisions between similar tools (use team preference)
- Mandated technology choices (decision already made)
- Emergency production issues (use monitoring tools)