Worktree Parallelization Skill

Purpose

This skill teaches Claude when and how to leverage git worktrees for parallel development across independent work streams.

Key Concept: Git worktrees allow multiple working directories from the same repository, each on different branches. This enables:

• True parallel development without conflicts
• Independent Claude instances in isolated contexts
• Separate branches managed simultaneously
• Clean separation of concerns

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When to Suggest Worktrees

✅ USE WORKTREES WHEN:

1. 3+ Independent Work Streams

   • Each stream modifies different files/modules
   • Minimal cross-dependencies
   • Each stream is substantial (multi-file, multi-step)

2. Long-Running Development

   • Tasks taking 30+ minutes each
   • Benefits from context preservation
   • Requires focused, uninterrupted work

3. Different Feature Contexts

   • Authentication + Payments + Analytics
   • Frontend + Backend + Infrastructure
   • Feature A + Bug Fix B + Refactor C

4. Potential Merge Complexity

   • Changes to shared files would conflict
   • Safer to develop in isolation
   • Complex merge logic best done manually

5. Parallel Testing/Experimentation

   • Testing different approaches simultaneously
   • A/B implementation comparisons
   • Rapid prototyping multiple solutions

❌ DO NOT USE WORKTREES FOR:

• Quick fixes (< 15 minutes)
• Single-file changes
• Tightly coupled changes requiring constant coordination
• When regular subagents are sufficient
• Simple, linear workflows

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Detection Pattern

When analyzing a user's task, extract work streams:

TASK: "Add user auth, payment processing, and analytics dashboard"

ANALYSIS:
Stream 1: User Authentication
  - Files: src/auth/, models/user.py, routes/auth.py
  - Dependencies: Database schema, session management
  - Estimated scope: Large (30+ min)

Stream 2: Payment Processing
  - Files: src/payments/, services/stripe.py, routes/checkout.py
  - Dependencies: External API (Stripe), webhooks
  - Estimated scope: Large (45+ min)

Stream 3: Analytics Dashboard
  - Files: src/analytics/, components/Dashboard.tsx, routes/analytics.py
  - Dependencies: Data aggregation, charting library
  - Estimated scope: Medium (25+ min)

VERDICT: ✅ 3 independent streams, each substantial, minimal overlap
→ SUGGEST WORKTREES

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How to Suggest

When you detect a pattern match, proactively suggest:

I can see this task has 3 independent work streams:
1. [Stream name] - [Files affected]
2. [Stream name] - [Files affected]
3. [Stream name] - [Files affected]

This is a great candidate for git worktree parallelization. I can:
- Set up separate worktrees for each stream
- Provide commands to launch Claude in each context
- Give you merge/cleanup instructions

Would you like me to set up worktrees? Run `/parallelize` or I can proceed with regular development.

IMPORTANT: Always ASK first. Never automatically create worktrees without user approval.

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Coordination Modes

When user approves, ask which coordination mode:

Mode 1: Independent (Simpler)

• Create worktrees with branches
• Provide terminal commands for user to open new Claude instances
• Each Claude works independently
• User manually merges branches when ready

Best for: Truly isolated features, experienced users, maximum control

Mode 2: Coordinated (Advanced)

• Create worktrees with branches
• Spawn Task agents in each worktree context
• Main Claude monitors progress
• Main Claude coordinates merging

Best for: Related features, complex coordination, automated workflow

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Example Usage Flow

USER: "Add OAuth login, subscription billing, and email notifications"

CLAUDE (via this skill):
  Detects 3 streams → Suggests worktrees → User approves

CLAUDE: "Which coordination mode?
  1. Independent - You manage each Claude instance
  2. Coordinated - I spawn agents and coordinate merging"

USER: "Independent"

CLAUDE (via /parallelize command):
  Creates worktrees → Generates terminal commands → Provides merge plan

USER: Opens 3 terminals, runs Claude in each

CLAUDE INSTANCES: Work independently on their streams

USER: Merges branches when ready

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Integration with Existing Workflows

• Subagents: Use for sub-tasks WITHIN each worktree
• Commands: Each worktree Claude has access to same commands
• Skills: All skills available in each context
• Git: Each worktree is independent git working directory

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Anti-Patterns

❌ Don't suggest worktrees for:

• "Fix typo in README"
• "Add a console.log"
• "Update dependency version"

❌ Don't create worktrees without user approval

❌ Don't use worktrees when subagents are sufficient

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Success Metrics

Worktrees are working well when:

• ✅ Parallel development is truly independent
• ✅ No merge conflicts despite simultaneous work
• ✅ Each stream completes without waiting on others
• ✅ Context switching overhead is eliminated

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Reference

See /parallelize command for implementation details.