# Using Git Worktrees

> Create isolated development workspaces with safety verification. Use when needing parallel development branches.

- Skill: `oimiragieo/using-git-worktrees` (Agent Skill, multi-file: 10 files)
- Install (CLI): `npx skillmds@latest add oimiragieo/using-git-worktrees`
- Raw SKILL.md: https://api.skillmd.com/api/skills/oimiragieo/using-git-worktrees/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: oimiragieo (https://skillmd.com/u/oimiragieo)
- Updated: 2026-09-10
- Page: https://skillmd.com/skills/oimiragieo/using-git-worktrees

---


# Using Git Worktrees

## Overview

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

**Core principle:** Systematic directory selection + safety verification = reliable isolation.

**Announce at start:** "I'm using the using-git-worktrees skill to set up an isolated workspace."

## Directory Selection Process

Follow this priority order:

### 1. Check Existing Directories

```bash
# Check in priority order
ls -d .worktrees 2>/dev/null     # Preferred (hidden)
ls -d worktrees 2>/dev/null      # Alternative
```

**If found:** Use that directory. If both exist, `.worktrees` wins.

### 2. Check CLAUDE.md

```bash
grep -i "worktree.*director" CLAUDE.md 2>/dev/null
```

**If preference specified:** Use it without asking.

### 3. Ask User

If no directory exists and no CLAUDE.md preference:

```
No worktree directory found. Where should I create worktrees?

1. .worktrees/ (project-local, hidden)
2. ~/.config/claude/worktrees/<project-name>/ (global location)

Which would you prefer?
```

## Safety Verification

### For Project-Local Directories (.worktrees or worktrees)

**MUST verify directory is ignored before creating worktree:**

```bash
# Check if directory is ignored (respects local, global, and system gitignore)
git check-ignore -q .worktrees 2>/dev/null || git check-ignore -q worktrees 2>/dev/null
```

**If NOT ignored:**

Per standard practice "Fix broken things immediately":

1. Add appropriate line to .gitignore
2. Commit the change
3. Proceed with worktree creation

**Why critical:** Prevents accidentally committing worktree contents to repository.

### For Global Directory (~/.config/claude/worktrees)

No .gitignore verification needed - outside project entirely.

## Creation Steps

### 1. Detect Project Name

```bash
project=$(basename "$(git rev-parse --show-toplevel)")
```

### 2. Create Worktree

```bash
# Determine full path
case $LOCATION in
  .worktrees|worktrees)
    path="$LOCATION/$BRANCH_NAME"
    ;;
  ~/.config/claude/worktrees/*)
    path="~/.config/claude/worktrees/$project/$BRANCH_NAME"
    ;;
esac

# Create worktree with new branch
git worktree add "$path" -b "$BRANCH_NAME"
cd "$path"
```

### 3. Run Project Setup

Auto-detect and run appropriate setup:

```bash
# 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:

```bash
# 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

| Situation                  | Action                      |
| -------------------------- | --------------------------- |
| `.worktrees/` exists       | Use it (verify ignored)     |
| `worktrees/` exists        | Use it (verify ignored)     |
| Both exist                 | Use `.worktrees/`           |
| Neither exists             | Check CLAUDE.md -> Ask user |
| Directory not ignored      | Add to .gitignore + commit  |
| Tests fail during baseline | Report failures + ask       |
| No package.json/Cargo.toml | Skip dependency install     |

## Common Mistakes

### Skipping ignore verification

- **Problem:** Worktree contents get tracked, pollute git status
- **Fix:** Always use `git check-ignore` before creating project-local worktree

### Assuming directory location

- **Problem:** Creates inconsistency, violates project conventions
- **Fix:** Follow priority: existing > CLAUDE.md > ask

### 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.

[Check .worktrees/ - exists]
[Verify ignored - git check-ignore confirms .worktrees/ is ignored]
[Create worktree: git worktree add .worktrees/auth -b feature/auth]
[Run npm install]
[Run npm test - 47 passing]

Worktree ready at /Users/dev/myproject/.worktrees/auth
Tests passing (47 tests, 0 failures)
Ready to implement auth feature
```

## Red Flags

**Never:**

- Create worktree without verifying it's ignored (project-local)
- Skip baseline test verification
- Proceed with failing tests without asking
- Assume directory location when ambiguous
- Skip CLAUDE.md check

**Always:**

- Follow directory priority: existing > CLAUDE.md > ask
- Verify directory is ignored for project-local
- Auto-detect and run project setup
- Verify clean test baseline

## Integration

**Called by:**

- **brainstorming** (Phase 4) - REQUIRED when design is approved and implementation follows
- Any skill needing isolated workspace

**Pairs with:**

- **finishing-a-development-branch** - REQUIRED for cleanup after work complete
- **executing-plans** or **subagent-driven-development** - Work happens in this worktree

## Iron Laws

1. **ALWAYS** verify `.gitignore` includes the worktree directory pattern before creating any worktree
2. **NEVER** create a worktree on a dirty working tree — stash or commit changes first
3. **ALWAYS** use project-local directories inside the project for worktree placement
4. **NEVER** delete a worktree with uncommitted changes without explicit user confirmation
5. **ALWAYS** run `git worktree prune` after removing worktrees to clean up stale metadata

## Anti-Patterns

| Anti-Pattern                               | Why It Fails                                    | Correct Approach                                 |
| ------------------------------------------ | ----------------------------------------------- | ------------------------------------------------ |
| Creating worktree with dirty working tree  | Uncommitted changes risk loss or confusion      | Stash or commit changes before creating worktree |
| Worktree outside project directory         | Not covered by .gitignore, leaks to VCS         | Use project-local paths inside the repo          |
| No .gitignore entry for worktree directory | Worktree files pollute `git status` output      | Add worktree path pattern to .gitignore first    |
| Deleting worktree without checking changes | Uncommitted work silently lost                  | Check for uncommitted changes before removal     |
| Forgetting `git worktree prune`            | Stale lock files block future worktree creation | Always prune after removing worktrees            |

## Memory Protocol (MANDATORY)

**Before starting:**
Read `.claude/context/memory/learnings.md`

**After completing:**

- New pattern -> `.claude/context/memory/learnings.md`
- Issue found -> `.claude/context/memory/issues.md`
- Decision made -> `.claude/context/memory/decisions.md`

> ASSUME INTERRUPTION: If it's not in memory, it didn't happen.