Show HN: Crystal a UI to Manage, Inspect, and Test Multiple Claude Code Sessions

Crystal is an Electron desktop application that lets you run, inspect, and test multiple Claude Code instances simultaneously using git worktrees. Crystal is an independent project created by Stravu. Stravu is the way AI-first teams collaborate.

Create multiple Claude Code sessions with a simple prompt, each running in its own git worktree

Track all changes with built-in git diff viewer showing additions, deletions, and commit history

Test your code instantly - run your worktree directly from Crystal

• 🚀 Parallel Sessions - Run multiple Claude Code instances at once
• 🌳 Git Worktree Isolation - Each session gets its own branch
• 💾 Session Persistence - Resume conversations anytime
• 🔧 Git Integration - Built-in rebase and squash operations
• 📊 Change Tracking - View diffs and track modifications
• 🔔 Notifications - Desktop alerts when sessions need input
• 🏗️ Run Scripts - Test changes instantly without leaving Crystal

• Claude Code installed and logged in or API key provided
• Git installed
• Git repository (Crystal will initialize one if needed)

• macOS: Download Crystal-{version}.dmg from the latest release
  • Open the DMG file and drag Crystal to your Applications folder
  • On first launch, you may need to right-click and select "Open" due to macOS security settings

You must create a project before you can proceed. A project should point to a git repository. If there is no repo in the folder you select one will be created.

Click "Create Session" and enter:

• Prompt: What you want Claude to do
• Worktree Name: Branch name (optional)
• Count: Number of parallel sessions

• 🟢 Running: Claude is working
• 🟡 Waiting: Needs your input
• ⚪ Stopped: Completed or paused
• Click any session to view or continue it

• Output: Formatted terminal output
• Changes: Git diffs of all modifications
• Terminal: Run tests or build scripts
• Messages: Raw JSON for debugging

Configure project-specific scripts in the project settings:

• Run scripts: Execute dev servers, test watchers, or any continuous processes
• Scripts run in the Terminal tab while Claude is working
• Each line runs sequentially - perfect for setup commands followed by servers
• All scripts stop automatically when the session ends

• Rebase from main: Pull latest changes
• Squash and rebase: Combine commits
• Preview commands before executing

We welcome contributions! Please see our Contributing Guidelines for details.

Crystal is open source software licensed under the MIT License.

Crystal is an independent project created by Stravu. Claude™ is a trademark of Anthropic, PBC. Crystal is not affiliated with, endorsed by, or sponsored by Anthropic. This tool is designed to work with Claude Code, which must be installed separately.