[BUG] Native installer installs x86_64 binary on Apple Silicon (arm64) Macs

[mikeschinkel]

Preflight Checklist

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

What's Wrong?

When installing Claude Code via the native installer (curl -fsSL https://claude.ai/install.sh | bash -s latest) on an Apple Silicon Mac, the installed binary is x86_64 instead of arm64.

The install script correctly detects arm64 and downloads the correct darwin-arm64 binary from GCS. However, after the script completes, the binary at ~/.local/bin/claude is x86_64.

This causes a Bun warning on every launch:

warn: CPU lacks AVX support, strange crashes may occur. Reinstall Bun or use *-baseline build:
  https://github.com/oven-sh/bun/releases/download/bun-v1.3.5/bun-darwin-x64-baseline.zip

What Should Happen?

The installer should install the arm64 binary on Apple Silicon Macs. Running file ~/.local/bin/claude should show Mach-O 64-bit executable arm64.

Error Messages/Logs

$ claude
warn: CPU lacks AVX support, strange crashes may occur. Reinstall Bun or use *-baseline build:
  https://github.com/oven-sh/bun/releases/download/bun-v1.3.5/bun-darwin-x64-baseline.zip

$ file ~/.local/bin/claude
/Users/mikeschinkel/.local/bin/claude: Mach-O 64-bit executable x86_64

$ uname -m
arm64

Steps to Reproduce

1. On an Apple Silicon Mac (M1/M2/M3/M4), confirm architecture:

   uname -m  # should return arm64

2. Remove any existing installation:

   rm -rf ~/.claude ~/.local/bin/claude
   npm uninstall -g @anthropic-ai/claude-code  # if previously installed via npm

3. Install via native installer:

   curl -fsSL https://claude.ai/install.sh | bash -s latest

4. Check the installed binary architecture:

   file ~/.local/bin/claude

5. Observe it shows x86_64 instead of arm64

Claude Model

None

Is this a regression?

I don't know

Last Working Version

No response

Claude Code Version

2.1.27

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

Root cause analysis:

The bug is not in install.sh — that script downloads the correct arm64 binary. The problem occurs when the script executes:

"$binary_path" install ${TARGET:+"$TARGET"}

This claude install subcommand installs the x86_64 binary instead of copying itself.

Workaround:

Manually download and replace the binary after installation:

curl -fsSL -o ~/.local/bin/claude "https://storage.googleapis.com/claude-code-dist-86c565f3-f756-42ad-8dfa-d59b1c096819/claude-code-releases/2.1.27/darwin-arm64/claude"
chmod +x ~/.local/bin/claude

Additional Information

• Hardware: M4 Mac Mini
• Verified the GCS bucket contains correct arm64 binary:

  curl -fsSL -o /tmp/claude-arm64-test "https://storage.googleapis.com/claude-code-dist-86c565f3-f756-42ad-8dfa-d59b1c096819/claude-code-releases/2.1.27/darwin-arm64/claude"
  file /tmp/claude-arm64-test
  # Returns: Mach-O 64-bit executable arm64

• The bundled Bun at ~/.claude/local/bin/bun is also x86_64

[github-actions]

Found 3 possible duplicate issues:

1. Bug: ARM64 binary replaced with x86_64 during install on Apple Silicon #13617
2. [Bug] Install subcommand downloads wrong architecture on Apple Silicon #15571
3. [BUG] False AVX Warning & Architecture Mismatch on Apple Silicon (M1) #20360

This issue will be automatically closed as a duplicate in 3 days.

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🤖 Generated with Claude Code

[github-actions]

This issue has been automatically closed as a duplicate of #13617.

If this is incorrect, please re-open this issue or create a new one.

🤖 Generated with Claude Code

[github-actions]

This issue has been automatically locked since it was closed and has not had any activity for 7 days. If you're experiencing a similar issue, please file a new issue and reference this one if it's relevant.