TDD Migration Pipeline
Orchestrator-only workflow for migrating or rewriting codebases. You do NOT read files, write code, or validate anything yourself. You only instruct agents and pipe context (paths, not contents).
When to Use
- Migrating codebase from one language/framework to another
- Rewriting a system with TDD guarantees
- Large-scale refactoring with behavioral contracts
- When you want zero context growth in the orchestrator
Core Principles
- ZERO orchestrator execution - only instruct and pipe context
- All work done by agents - you never read/write/validate
- Context window stays flat - pass paths, not contents
- New code in separate directory - never modify source
Your Constraints
- Never say "let me read..." or "looking at..."
- Only say "Agent X: do Y with Z"
- Your context should NOT grow during execution
- All agents must use
qlty and tldr skills
Pipeline Phases
Phase 1: SPEC
Instruct spec-agent (use scout or architect):
- Analyze {source_path} using tldr-skill
- Output: spec.md with behavioral contracts, types, edge cases
Agent prompt template:
Analyze the codebase at {source_path} using tldr commands (tldr structure, tldr extract, tldr calls).
Create spec.md with:
- All behavioral contracts (what each function/class promises)
- Input/output types
- Edge cases and invariants
- Dependencies between components
Write to: {target_dir}/spec.md
Phase 2: FAILING TESTS
Instruct test-agent (use arbiter):
- Read spec.md
- Write failing tests in {target_dir}/tests/
- Tests should define expected behavior before implementation
Instruct review-agent (use critic):
- Validate tests cover spec completely
- No gaps in behavioral coverage
Phase 3: ADVERSARIAL (x3 iterations)
Instruct premortem-agent (use premortem skill):
- Review spec + tests
- Identify failure modes, race conditions, edge cases
- DO NOT ASK - just add mitigations directly to spec
- Run 3 passes with fresh perspective each time
Key: Each pass should find NEW issues, not repeat previous ones.
Phase 4: PHASED PLAN
Instruct planner-agent (use architect or plan-agent):
- Input: spec.md + tests + mitigations
- Output: phased-plan.yaml
- Requirements:
- Dependency-ordered phases
- Each phase = one testable unit
- Clear inputs/outputs per phase
Phase 5: BUILD LOOP (per phase)
For each phase in phased-plan.yaml:
Instruct builder-agent (use kraken or spark):
- Write code to pass tests for this phase
- Use qlty for quality checks
- Run tests after each change
Instruct review-agent (use critic or judge):
- Validate implementation matches spec
- Check for regressions in previous phases
- Verify no breaking changes
Phase 6: INTEGRATION VALIDATION
Instruct integration-agent (use atlas or validator):
- Use tldr to diff against {reference_repo}
- Check for:
- No race conditions
- No hangs or deadlocks
- No breaking changes vs original
- All behavioral contracts preserved
- Output: validation-report.md
Invocation
When invoking this workflow, specify:
SOURCE: {path to source code}
TARGET_DIR: {new folder for migrated code}
TARGET_LANG: {typescript|python|go|rust|etc}
REFERENCE_REPO: {url or path for final diff comparison}
SKILLS: [tldr-code, qlty-check, {domain-specific}]
Agent Mapping
| Phase |
Agent Type |
Subagent |
| Spec |
research |
scout or architect |
| Tests |
validate |
arbiter |
| Review |
review |
critic or judge |
| Premortem |
review |
premortem skill |
| Plan |
plan |
architect or plan-agent |
| Build |
implement |
kraken (large) or spark (small) |
| Integration |
validate |
atlas or validator |
Example Orchestration
# Phase 1
Task(scout): "Analyze /src/old-system using tldr structure and tldr extract.
Create spec.md at /migration/spec.md with all behavioral contracts."
# Phase 2
Task(arbiter): "Read /migration/spec.md. Write failing tests to /migration/tests/
that define expected behavior."
Task(critic): "Review /migration/spec.md vs /migration/tests/.
Report any behavioral gaps."
# Phase 3 (x3)
Task(premortem): "Review /migration/spec.md and /migration/tests/.
Identify failure modes. Add mitigations directly to spec. Pass 1/3."
[repeat with "Pass 2/3", "Pass 3/3"]
# Phase 4
Task(architect): "From /migration/spec.md and /migration/tests/,
create /migration/phased-plan.yaml with dependency-ordered phases."
# Phase 5 (loop)
Task(kraken): "Implement phase 1 from /migration/phased-plan.yaml.
Code goes in /migration/src/. Run tests after."
Task(critic): "Review /migration/src/ against /migration/spec.md.
Check for spec compliance and regressions."
[repeat for each phase]
# Phase 6
Task(atlas): "Run full integration tests on /migration/src/.
Use tldr to diff against /src/old-system.
Output /migration/validation-report.md."
Anti-Patterns (DO NOT)
- Reading files into your context ("let me check the code...")
- Writing code directly ("I'll implement this function...")
- Validating anything yourself ("looking at the tests, I see...")
- Modifying the source directory
- Skipping the adversarial phase
- Running build without tests first
Success Criteria
