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Sandbox any macOS app — only your project directory stays accessible

69 starsTypeScript

Bx – macOS native sandbox for AI and coding tools

by holtwick·Apr 7, 2026·8 points·0 comments
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AI Analysis

●●SolidSolve My ProblemBig BrainNiche Gem

Native macOS sandboxing stops AI agents from reading your SSH keys without Docker overhead.

Strengths
  • •Uses sandbox-exec profiles to restrict file access without heavy VM overhead.
  • •Gitignore-like .bxignore syntax handles secrets like .env files within allowed directories.
  • •Automatically blocks sensitive defaults like ~/.ssh and ~/Documents out of the box.
Weaknesses
  • •Relies on private Apple APIs that may break in future macOS updates.
  • •No network isolation means AI tools can still exfiltrate data.
Target Audience

macOS developers using AI coding agents

Similar To

Sandboxie · Docker Desktop · OrbStack

Post Description

Wrapper around Apple's macOS sandbox-exec tool, which usually sandboxes native apps. It is "allow-first" i.e. it will not overprotect everything, just crucial information and therefore allows most tools to run without issues. Limiting is done using a .gitignore like file schema. Further TOML config options available.

I built it because Docker sandboxing requires config and planning. Build in sandboxing of AI tools instead is limited to the very tools themselves, instead I wanted to have a simple cage around Claude running inside VSCode. Also needed to protect files inside a folder like .env.local or keys.

Install via: brew install holtwick/tap/bx

Run like: bx claude .

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Niche GemSlick
hulryung
103mo ago