[BUG] Sandbox: bwrap: Can't bind mount /oldroot/ on /newroot/: Operation not permitted

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?

When using the sandbox, I intermittently get

bwrap: Can't bind mount /oldroot/ on /newroot/: Operation not permitted

Guessing: a slow to initialize temp filesystem isn't always ready before the bwrap command is triggered

What Should Happen?

It should not error

Error Messages/Logs

Steps to Reproduce

Launch with sandbox a lot of times and try to run Bash commands quickly on a separate non-cwd directory.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Latest

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_