Code Necromancer

Tagline: Raise dead codebases from the grave

Systematic framework for understanding, resurrecting, and modernizing legacy codebases.

When to Activate

✅ Use when:

• Inheriting a codebase with 5+ repos and no documentation
• Resurrecting a product dormant for 2+ years
• Joining a company with significant technical debt and tribal knowledge loss
• Performing due diligence on acquired codebases
• Modernizing legacy systems without breaking existing functionality

❌ NOT for:

• Greenfield projects (start fresh instead)
• Well-documented active codebases
• Simple bug fixes in maintained systems

The Three Phases

Phase 1: ARCHAEOLOGY

Objective: Create a complete map before touching anything.

Process: Inventory → Deep Scan → Cross-Reference → Visualize → Assess

→ See references/archaeology-guide.md for detailed techniques.

Phase 2: RESURRECTION

Objective: Get the system running in development.

Process: Audit Dependencies → Map Environment → Check Infrastructure → Write Tests → Document Blockers

→ See references/integration-test-patterns.md for resurrection test patterns.

Phase 3: REJUVENATION

Objective: Modernize while maintaining feature parity.

Process: Security First → Infrastructure (containerize, CI/CD) → Code Quality → Architecture

Key Commands

# List all repos in org
gh repo list ORG --limit 1000 --json name,primaryLanguage,pushedAt

# Dependency analysis
npm audit && npm outdated      # Node.js
pip list --outdated && safety check  # Python
go mod graph                    # Go

# Find env vars in code
grep -rn 'process\.env\|os\.environ' --include="*.js" --include="*.py"

→ See references/framework-detection.md for framework/stack identification. → See references/infrastructure-mapping.md for cloud resource discovery. → See references/dependency-patterns.md for dependency detection.

Anti-Patterns to Avoid

1. Premature Resurrection

What it looks like: Running npm install before reading any code Why it's wrong: You'll fix the same bug 5 times; dependencies have changed Fix: Complete archaeology first; understand before touching

2. Scope Creep

What it looks like: "Let's also refactor while we're here" Why it's wrong: Scope explosion; never actually resurrect Fix: Strict phase separation; refactoring is Phase 3

3. Big Bang Updates

What it looks like: Update all dependencies in one commit Why it's wrong: Something breaks, no idea what Fix: Update incrementally; test after each

4. Ignoring Tests

What it looks like: "It runs, ship it" Why it's wrong: Regression city; no baseline for changes Fix: Write resurrection tests as you go; they prove progress

5. Undocumented Changes

What it looks like: "I fixed it but forgot what I changed" Why it's wrong: Tribal knowledge returns; next person is you in 6 months Fix: Document everything you learn and change

6. Trusting Old Documentation

What it looks like: Following README from 2019 Why it's wrong: APIs change, services get deprecated Fix: Verify every instruction; documentation lies

Success Metrics

Archaeology Complete When:

• All repos cataloged with metadata
• Dependency graph visualized
• Architecture diagram created
• Core vs peripheral repos identified
• Missing pieces documented

Resurrection Complete When:

• All services start locally
• Services can communicate with each other
• Integration tests pass
• At least one full user flow works

Rejuvenation Complete When:

• No critical security vulnerabilities
• All dependencies reasonably current
• CI/CD pipeline working
• Documentation current
• Team can develop new features

References

→ references/archaeology-guide.md - Deep code archaeology techniques → references/dependency-patterns.md - Dependency detection across ecosystems → references/framework-detection.md - Framework/stack identification → references/infrastructure-mapping.md - Cloud resource discovery → references/integration-test-patterns.md - Resurrection test patterns

Templates

→ templates/repo-inventory.json - Repository catalog → templates/archaeology-report.md - Phase 1 output → templates/resurrection-plan.md - Phase 2 output → templates/rejuvenation-roadmap.md - Phase 3 output