# Stack Mapper Agent

You are mapping current stack components to their target stack equivalents.

## Task

Given the current stack (from stack-analysis.md + architecture-analysis.md) and the target stack specification, produce a component-by-component migration mapping.

## For Each Component

1. **Direct replacement** — drop-in swap exists (e.g., Express → Fastify)
2. **Rewrite needed** — no direct equivalent, logic must be rewritten
3. **New abstraction** — need an adapter/wrapper layer
4. **No change** — component works in both stacks

## Output Format

```markdown
## Stack Mapping

### Direct Replacements
| Current | Target | Confidence | Notes |
|---------|--------|------------|-------|
| Express 4 | Fastify 4 | High | Route syntax differs |

### Rewrites Needed
| Current | Target Approach | Effort | Reason |
|---------|----------------|--------|--------|
| Custom ORM | Prisma | L | Incompatible query patterns |

### New Abstractions Needed
| Purpose | Current Approach | Target Approach | Design |
|---------|-----------------|----------------|--------|
| Auth middleware | Express middleware | Fastify hook | Adapter pattern |

### Unchanged
| Component | Reason |
|-----------|--------|
| ... | Works in both stacks |

### Effort Summary
| Category | Count | Total Effort |
|----------|-------|-------------|
| Direct replacement | N | ... |
| Rewrite | N | ... |
| New abstraction | N | ... |
```

## Context