Using Git Worktree

Using Git Worktrees (Bare Repo Setup)

Overview

Git worktrees create isolated workspaces sharing the same repository, allowing work on multiple branches simultaneously without switching.

Core principle: Find bare repo root + create sibling worktree = reliable isolation.

Announce at start: "I'm using the Using Git Worktrees skill to set up an isolated workspace."

Bare Repo Structure

This skill assumes a bare git repository setup:

project-root/
├── .bare/          # Actual git repository
├── .git            # Points to .bare
├── main/           # Worktree for main branch
├── feature-a/      # Worktree for feature-a branch
└── feature-b/      # Worktree for feature-b branch

Worktrees are created as siblings at the root level, not in subdirectories.

Bare Repo Detection

1. Find Bare Repo Root

# Walk up directory tree to find .bare directory
current_dir=$(pwd)
bare_root=""

while [ "$current_dir" != "/" ]; do
  if [ -d "$current_dir/.bare" ]; then
    bare_root="$current_dir"
    break
  fi
  current_dir=$(dirname "$current_dir")
done

if [ -z "$bare_root" ]; then
  echo "Error: Not in a bare git repository setup (no .bare directory found)"
  exit 1
fi

If .bare not found: Report error - this skill requires bare repo setup.

Creation Steps

1. Navigate to Bare Root

cd "$bare_root"

2. Create Worktree

# Create worktree as sibling directory at bare root
git worktree add "$BRANCH_NAME" -b "$BRANCH_NAME"
cd "$BRANCH_NAME"

Note: No .gitignore verification needed - worktrees at bare root are managed by .bare/, not tracked by individual worktree git status.

3. Run Project Setup

Auto-detect and run appropriate setup:

# Node.js
if [ -f package.json ]; then npm install; fi

# Rust
if [ -f Cargo.toml ]; then cargo build; fi

# Python
if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
if [ -f pyproject.toml ]; then poetry install; fi

# Go
if [ -f go.mod ]; then go mod download; fi

4. Verify Clean Baseline

Run tests to ensure worktree starts clean:

# Examples - use project-appropriate command
npm test
cargo test
pytest
go test ./...

If tests fail: Report failures, ask whether to proceed or investigate.

If tests pass: Report ready.

5. Report Location

Worktree ready at <full-path>
Tests passing (<N> tests, 0 failures)
Ready to implement <feature-name>

Quick Reference

Common Mistakes

Not detecting bare repo root

• Problem: Creates worktree in wrong location
• Fix: Always walk up to find .bare/ directory first

Proceeding with failing tests

• Problem: Can't distinguish new bugs from pre-existing issues
• Fix: Report failures, get explicit permission to proceed

Hardcoding setup commands

• Problem: Breaks on projects using different tools
• Fix: Auto-detect from project files (package.json, etc.)

Example Workflow

You: I'm using the Using Git Worktrees skill to set up an isolated workspace.

[Current directory: /Users/hmps/myproject/main/src]
[Walk up tree looking for .bare/]
[Found .bare at /Users/hmps/myproject/]
[Navigate to bare root: cd /Users/hmps/myproject]
[Create worktree: git worktree add feature-auth -b feature-auth]
[Navigate to worktree: cd feature-auth]
[Run npm install]
[Run npm test - 47 passing]

Worktree ready at /Users/hmps/myproject/feature-auth
Tests passing (47 tests, 0 failures)
Ready to implement auth feature

Red Flags

Never:

• Create worktree without finding .bare/ root first
• Skip baseline test verification
• Proceed with failing tests without asking
• Assume you're at bare root without checking

Always:

• Walk up directory tree to find .bare/
• Create worktree at bare root level as sibling
• Auto-detect and run project setup
• Verify clean test baseline

Integration

Called by:

• skills/collaboration/brainstorming (Phase 4)
• Any skill needing isolated workspace

Pairs with:

• skills/collaboration/finishing-a-development-branch (cleanup)
• skills/collaboration/executing-plans (work happens here)