[BUG]

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?

Details: desktop app version (1.3109.0) and macOS version (15.3.1 beta)
I am experiencing a critical issue with Claude Desktop on my Mac. The Claude Code mode crashes and closes the entire app after approximately 5 seconds every time I try to open it.

Device: Mac Mini (Mac14,3), arm64, 8GB RAM
OS: macOS 26.3.1 (Build 25D771280a) — beta
Claude Desktop version: 1.3109.0
Claude Code CLI version: 2.1.112
What works: Regular chat and Cowork mode work perfectly fine.

What doesn't work: Claude Code mode — the entire app closes after ~5 seconds.

Crash cause: macOS diagnostic report shows 2147 MB written to disk in 78 seconds, exceeding macOS 26 disk write limits. The app gets terminated by the OS.

Steps already tried: moved app to /Applications, deleted VM cache, removed conflicting Codex.app, restarted Mac. Issue persists.

What Should Happen?

The issue appears to be that Claude Code's VM initialization writes approximately 2GB of data to disk in under 80 seconds, which violates macOS 26's disk write throttling limits. A few possible fixes Anthropic could investigate:

Reduce the amount of data written during VM initialization, or split it into smaller chunks over time to stay within macOS disk write limits.
Pre-build or compress the VM disk image so it requires less writing on first launch.
Request a macOS entitlement exemption from disk write throttling for the Claude Desktop app, similar to how other virtualization apps (like Parallels or VMware) handle it.
Test and certify Claude Desktop compatibility with macOS 26 beta builds.

Error Messages/Logs

Claude Code mode should open and remain stable, allowing me to use the coding interface. Instead, the entire Claude Desktop app closes after approximately 5 seconds. macOS diagnostic report shows the app is killed due to excessive disk writes: 2147.50 MB written in 78 seconds (27.45 MB/sec), exceeding the macOS 26 limit of 24.86 KB/sec. The crash is triggered by the VM initialization process when Claude Code mode starts.

Steps to Reproduce

Steps to Reproduce:

Open Claude Desktop (v1.3109.0) on macOS 26.3.1 beta (Mac Mini, arm64, 8GB RAM)
Click on the Claude Code mode button in the app
Wait approximately 5 seconds
The entire Claude Desktop app closes automatically
Check /Library/Logs/DiagnosticReports/ — a .diag file is created showing Event: disk writes with 2147 MB written in 78 seconds

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Claude Desktop version: 1.3109.0 - Claude Code CLI version: 2.1.112

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_