parallel-implementation

name	parallel-implementation
description	Implements top 3-5 priority GitHub issues in parallel using git worktrees and separate subagents, then creates PRs for each. Use when you want to tackle multiple issues simultaneously.
disable-model-invocation	true
argument-hint	[--max-parallel N] [--priority P] [--label L] [--dry-run] [--no-push] [--no-pr]
allowed-tools	Bash(gh *), Bash(git *), Subagent, Task, TaskWrite, TaskCheck, AskUser, Read, Write, View, FindFiles, SearchContent, StringReplaceLsp, ExecuteCommand, SubmitPlan

Parallel Implementation Skill

Implements the top 3-5 priority GitHub issues in parallel by creating separate git worktrees for each issue, spawning dedicated subagents to work on them simultaneously, and creating PRs for each completed implementation.

Quick Start

/parallel-implementation

This will:

1. Identify the top 3-5 priority issues
2. Create git worktrees for each issue
3. Spawn subagents to implement each issue in parallel
4. Monitor progress and create PRs as they complete

Options

• --max-parallel N: Maximum number of issues to work in parallel (default: 5)
• --priority P: Filter by priority label (e.g., critical, high, medium, low)
• --label L: Filter by specific label
• --dry-run: Show what would be done without actually creating worktrees
• --no-push: Skip pushing branches to remote
• --no-pr: Skip creating PRs
• --branch-name-format FORMAT: Custom branch name format (default: issue-{number}-{slug})

How It Works

Phase 1: Issue Discovery

1. Uses gh issue list to fetch open issues
2. Prioritizes issues based on:
   • Priority labels (critical > high > medium > low)
   • Creation date (older issues first)
   • Comment count (more discussion = higher priority)
3. Filters for implementable issues (excludes questions, duplicates, etc.)
4. Selects top 3-5 issues based on priority score

Phase 2: Worktree Setup

For each selected issue:

# Create a feature branch
git checkout -b issue-{number}-{slug}

# Create a worktree in a sibling directory
git worktree add ../issue-{number}-{slug} -b issue-{number}-{slug}

Worktrees are created in the parent directory to avoid conflicts:

• ../issue-123-feature-description
• ../issue-456-bug-fix
• etc.

Phase 3: Parallel Execution

Spawns separate subagents for each worktree:

Subagent 1: ../issue-123-feature-description
Subagent 2: ../issue-456-bug-fix
Subagent 3: ../issue-789-performance

Each subagent:

• Analyzes the issue requirements
• Implements the solution
• Runs tests and linting
• Ensures code quality

Phase 4: PR Creation

When a subagent completes successfully:

# Navigate to worktree
cd ../issue-123-feature-description

# Push branch to remote
git push -u origin issue-123-feature-description

# Create PR linked to issue
gh pr create \
  --title "Fix #123: Issue Title" \
  --body "Closes #123" \
  --base main \
  --label "auto-generated"

Phase 5: Cleanup

After PR creation:

• Removes the worktree to free up space
• Switches back to original branch
• Updates the main worktree to stay in sync

Issue Prioritization

Issues are scored using a priority matrix:

• Priority Label: 100 (critical), 75 (high), 50 (medium), 25 (low)
• Age: Up to 10 points (older = higher)
• Comments: Up to 5 points (more discussion = higher)
• Assignee: +5 points if assigned

Excluded issues:

• Issues with "question", "duplicate", or "wontfix" labels
• Issues without a clear implementation path
• Issues requiring coordination with other issues

Parallel Execution Strategy

The skill ensures parallel workability by:

1. File Isolation: Each subagent works in a separate worktree with its own working directory
2. Branch Isolation: Each issue gets its own git branch
3. Conflict Prevention: Issues that modify the same files are not selected for parallel execution
4. Independent Execution: Subagents run completely independently

Subagent Capabilities

Each subagent has access to:

• All file operations (read, write, edit)
• Search and code analysis
• Test execution
• Git operations within their worktree
• Ability to spawn additional subagents if needed

Subagents are configured with:

• Clear issue context (title, description, labels, comments)
• Repository conventions and patterns
• Quality standards (lint, test, typecheck)

Monitoring and Progress

The skill monitors:

• Subagent status (running, completed, failed)
• File changes in each worktree
• Test results
• Git status (committed changes, uncommitted changes)

Progress is reported in real-time:

[1/5] Issue #123: Feature X
  Status: In Progress
  Subagent: Running
  Files modified: 5
  Last activity: 2m ago

[2/5] Issue #456: Bug Y
  Status: Completed
  Subagent: Finished
  PR created: https://github.com/user/repo/pull/123

Error Handling

If a subagent fails:

1. Logs the error with context
2. Offers to retry with different approach
3. Continues with other subagents
4. Collects failed issues for manual review

Safety Features

• Dry Run Mode: Preview actions without executing
• Interactive Confirmation: Confirm before creating worktrees
• Backup Check: Ensures main branch is clean
• Worktree Cleanup: Automatic cleanup of completed worktrees
• Rollback: Ability to delete branches and worktrees if needed

Example Usage

Basic Implementation

# Implement top 5 priority issues
/parallel-implementation

With Filtering

# Only high-priority issues, max 3 in parallel
/parallel-implementation --priority high --max-parallel 3

Dry Run

# Preview what would be done
/parallel-implementation --dry-run

Custom Branch Naming

# Custom branch name format
/parallel-implementation --branch-name-format "feat/{number}-{slug}"

Output Format

The skill provides structured output:

================================================================================
PARALLEL IMPLEMENTATION: EXECUTION PLAN
================================================================================

Selected Issues (3 total):

1. Issue #123: Feature X
   Priority: critical
   Branch: issue-123-feature-x
   Worktree: ../issue-123-feature-x
   Estimated effort: 2-3 hours

2. Issue #456: Bug Y
   Priority: high
   Branch: issue-456-bug-y
   Worktree: ../issue-456-bug-y
   Estimated effort: 1-2 hours

3. Issue #789: Performance Z
   Priority: medium
   Branch: issue-789-performance-z
   Worktree: ../issue-789-performance-z
   Estimated effort: 3-4 hours

────────────────────────────────────────────────────────────────────────────────
EXECUTING PHASE 1: Creating Worktrees...
────────────────────────────────────────────────────────────────────────────────

Created worktree: ../issue-123-feature-x
Created worktree: ../issue-456-bug-y
Created worktree: ../issue-789-performance-z

────────────────────────────────────────────────────────────────────────────────
EXECUTING PHASE 2: Spawning Subagents...
────────────────────────────────────────────────────────────────────────────────

Spawned subagent for Issue #123 (PID: 12345)
Spawned subagent for Issue #456 (PID: 12346)
Spawned subagent for Issue #789 (PID: 12347)

────────────────────────────────────────────────────────────────────────────────
EXECUTING PHASE 3: Monitoring Progress...
────────────────────────────────────────────────────────────────────────────────

[1/3] Issue #123: Feature X
  Status: ✅ Completed
  PR: https://github.com/user/repo/pull/456
  Worktree removed: ../issue-123-feature-x

[2/3] Issue #456: Bug Y
  Status: ✅ Completed
  PR: https://github.com/user/repo/pull/457
  Worktree removed: ../issue-456-bug-y

[3/3] Issue #789: Performance Z
  Status: ⏳ In Progress
  Subagent: Running (45m elapsed)
  Files modified: 12

================================================================================
SUMMARY
================================================================================

Completed: 2/3
In Progress: 1/3
Failed: 0/3

PRs Created:
- #456: Fix #123 - Feature X
- #457: Fix #456 - Bug Y

Next Steps:
- Wait for Issue #789 completion
- Review and merge completed PRs

Integration with Other Skills

This skill works well with:

• pr-automation: For reviewing and merging the created PRs
• parallel-issues: For more advanced issue planning and analysis
• simplify: For code quality review before PR creation

Troubleshooting

Worktree Already Exists

If a worktree with the same path exists:

# Remove existing worktree
git worktree remove ../issue-123-feature-x

# Re-run the skill

Subagent Fails

If a subagent fails:

1. Check the worktree manually: cd ../issue-123-feature-x
2. Review the error logs
3. Run /parallel-implementation again to retry
4. The skill will skip completed issues

PR Creation Fails

If PR creation fails:

1. Push the branch manually: cd ../issue-123-feature-x && git push
2. Create PR manually: gh pr create --title "..." --body "..."
3. Remove worktree: git worktree remove ../issue-123-feature-x

Best Practices

1. Start Small: Use --max-parallel 2 or --dry-run first
2. Filter by Priority: Use --priority high for critical issues only
3. Review Issues: Ensure selected issues are well-defined and implementable
4. Monitor Progress: Watch the real-time output to catch issues early
5. Clean Up: Worktrees are removed automatically after PR creation

Requirements

• GitHub CLI (gh) installed and authenticated
• Git worktrees supported (Git 2.5+)
• Write access to the repository
• At least 3-5 issues available to implement