Migrate To Deltas

Migrate to Delta-Based Workflow

Migrate an existing katachi project from feature-centric to delta-centric development.

Context

You must load the following skills before proceeding.

Skills

• katachi:framework-core - Workflow principles and task management

What This Does

Transforms your project structure:

• FEATURES.md → DELTAS.md (converts feature entries to deltas)
• feature-specs/.md → delta-specs/.md (working documents)
• feature-designs/.md → delta-designs/.md (working documents)
• Generates new nested feature documentation from deltas
• Inlines dependencies into DELTAS.md entries as **Depends on** fields
• Removes BACKLOG.md (items optionally converted to deltas)

Pre-Check

Verify this is a katachi project:

• Check for docs/planning/FEATURES.md
• Check for docs/planning/DEPENDENCIES.md (if exists, migrate dependencies inline into DELTAS.md entries)
• If FEATURES.md not found, this is not a katachi project or already migrated

Warn user:

"This will restructure your katachi project files.

Changes:
- Creates: delta-specs/, delta-designs/, delta-plans/
- Transforms: FEATURES.md → DELTAS.md
- Moves: feature-specs/ → delta-specs/
- Moves: feature-designs/ → delta-designs/
- Generates: New nested feature-specs/ and feature-designs/
- Inlines: Dependencies into DELTAS.md entries
- Removes: BACKLOG.md

Continue with migration? [Y/N]"

If user declines, exit.

Migration Process

Use parallel task execution for independent operations.

Phase 1: Create Tasks

Create all migration tasks with dependencies:

# Task 1: Create directory structure (no deps)
TaskCreate(
    subject="Create delta directory structure",
    description="Create delta-specs/, delta-designs/, delta-plans/ directories"
)

# Task 2: Transform FEATURES.md → DELTAS.md (no deps)
TaskCreate(
    subject="Transform FEATURES to DELTAS",
    description="Convert FEATURES.md entries to DELTAS.md with DLT-XXX IDs"
)

# Task 3: Move feature-specs/ → delta-specs/ (depends on 1, 2)
TaskCreate(
    subject="Move feature specs to delta specs",
    description="Rename and move feature-specs/*.md → delta-specs/*.md"
)

# Task 4: Move feature-designs/ → delta-designs/ (depends on 1, 2)
TaskCreate(
    subject="Move feature designs to delta designs",
    description="Rename and move feature-designs/*.md → delta-designs/*.md"
)

# Task 5: Inline dependencies into DELTAS.md (depends on 2)
TaskCreate(
    subject="Inline dependencies into DELTAS.md entries",
    description="Add **Depends on** fields to each delta entry in DELTAS.md"
)

# Task 6: Remove BACKLOG.md (depends on 2)
TaskCreate(
    subject="Remove backlog",
    description="Archive or delete BACKLOG.md"
)

# Task 7: Analyze deltas to identify domains (depends on 3, 4)
TaskCreate(
    subject="Analyze capability domains",
    description="Group deltas into capability domains for feature docs"
)

# Task 8: Generate feature-specs/ structure (depends on 7)
TaskCreate(
    subject="Generate feature specs",
    description="Create nested feature-specs/ with READMEs"
)

# Task 9: Generate feature-designs/ structure (depends on 7)
TaskCreate(
    subject="Generate feature designs",
    description="Create nested feature-designs/ with READMEs"
)

Phase 2: Execute Tasks

Execute tasks respecting dependencies. Tasks without dependencies can run in parallel.

Task 1: Create Directory Structure

mkdir -p docs/delta-specs
mkdir -p docs/delta-designs
mkdir -p docs/delta-plans

Task 2: Transform FEATURES.md → DELTAS.md

Read FEATURES.md, convert to DELTAS.md format:

Old format (FEATURES.md):

### CATEGORY-001: Feature name
**Status**: ✓ Defined
**Complexity**: Medium
**Description**: Feature description...

New format (DELTAS.md):

### DLT-001: Feature name
**Status**: ✓ Defined
**Complexity**: Medium
**Description**: Feature description...

Mapping:

• Create sequential DLT-NNN IDs
• Preserve status, complexity, description
• Track mapping (DLT-NNN → DLT-NNN) for dependency updates

Write to docs/planning/DELTAS.md.

Task 3: Move feature-specs/ → delta-specs/

For each file in docs/feature-specs/:

• Read content
• Update header (FEATURE-ID → DLT-ID using mapping)
• Add "Detected Impacts" section template at end
• Write to docs/delta-specs/DLT-NNN.md

Task 4: Move feature-designs/ → delta-designs/

For each file in docs/feature-designs/:

• Read content
• Update header (FEATURE-ID → DLT-ID using mapping)
• Add "Detected Impacts" section template at end
• Write to docs/delta-designs/DLT-NNN.md

Task 5: Inline Dependencies into DELTAS.md

Add **Depends on**: DLT-XXX, DLT-YYY (or None) to each delta entry in DELTAS.md, deriving from the old DEPENDENCIES.md matrix or FEATURES.md dependency info.

Task 6: Remove BACKLOG.md

Ask user: "What should we do with BACKLOG.md?"

• Option 1: Delete (items are outdated)
• Option 2: Archive to docs/archive/BACKLOG.md
• Option 3: Convert to deltas (prompt for each item)

Execute chosen option.

Task 7: Analyze Deltas to Identify Domains

Read all delta-specs/ files:

• Analyze descriptions, user stories
• Group into capability domains
• Suggest domain structure:

  auth/
    login.md
    oauth.md
  projects-management/
    listing.md
    creation.md
  

Present proposed structure to user for approval.

Task 8: Generate feature-specs/ Structure

Create nested structure:

mkdir -p docs/feature-specs

For each domain:

1. Create domain folder: docs/feature-specs/[domain]/
2. Create README.md (domain overview)
3. For each sub-capability in domain:
   • Create capability.md
   • Synthesize from related delta specs
   • Include "Related Deltas" section
4. Create top-level README.md (domain index)

Task 9: Generate feature-designs/ Structure

Mirror feature-specs/ structure:

mkdir -p docs/feature-designs

For each domain:

1. Create domain folder: docs/feature-designs/[domain]/
2. Create README.md (domain overview)
3. For each sub-capability:
   • Create capability.md
   • Synthesize from related delta designs
   • Include "Related Deltas" section
4. Create top-level README.md (domain index)

Phase 3: Cleanup

After all tasks complete:

1. Backup old structure (optional):

   mkdir -p docs/archive/pre-migration
   mv docs/planning/FEATURES.md docs/archive/pre-migration/
   mv docs/feature-specs/ docs/archive/pre-migration/
   mv docs/feature-designs/ docs/archive/pre-migration/
   

2. Verify new structure:

   • Check DELTAS.md exists
   • Check delta-specs/ has all files
   • Check delta-designs/ has all files
   • Check feature-specs/ has nested structure
   • Check feature-designs/ has nested structure
   • Check dependencies inlined in DELTAS.md

3. Present summary:

   "Migration complete!
   
   Deltas: N (from N features)
   Delta specs: N files
   Delta designs: N files
   Feature domains: N
   
   New structure:
   - docs/planning/DELTAS.md
   - docs/delta-specs/ (N files)
   - docs/delta-designs/ (N files)
   - docs/feature-specs/ (N domains)
   - docs/feature-designs/ (N domains)
   
   Next steps:
   - Use /add-delta to add new work
   - Use /spec-delta, /design-delta, /plan-delta, /implement-delta
   - Use /reconcile-delta to update feature docs after implementation"
   

Error Handling

Already migrated:

• If DELTAS.md exists, warn and exit
• Suggest this might already be a delta-based project

Missing files:

• If FEATURES.md missing, can't migrate
• Explain what's needed

Partial failure:

• If a task fails, report which tasks completed
• Allow user to retry or rollback from backup

Workflow

This is an automated migration with user approval:

• Check pre-conditions
• Warn user about changes
• Create tasks with dependencies
• Execute tasks in parallel where possible
• Generate new feature docs from deltas
• Verify and cleanup
• Present summary