[BUG] Native installation causes system freeze with Python joblib/multiprocessing on Apple Silicon

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

After switching from npm installation to native binary installation (v2.1.29), running Python code that uses joblib or multiprocessing via Claude Code causes the system to freeze/become unresponsive.

Environment:

• macOS on Apple Silicon (M2)
• Claude Code 2.1.29 (native ARM64 binary)
• RAM: 8 GB
• Python with joblib/multiprocessing

The same code worked fine with npm installation.

What Should Happen?

System should remain responsive when running Python multiprocessing code.

Error Messages/Logs

No error messages - system freezes, requires force restart.

Steps to Reproduce

1. Install Claude Code via native installer
2. Run Python code using joblib/multiprocessing via bash
3. System becomes unresponsive

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

v2.1.29

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_