landstrip 0.8.3

Sandbox for coding agents with parametrized state
landstrip-0.8.3 is not a library.

landstrip

landstrip runs a command in an OS-level sandbox using Landlock LSM on Linux, Seatbelt on macOS, and LPAC AppContainer on Windows. It accepts the Anthropic Sandbox Runtime JSON subset as the policy.

Backends compared:

Area macOS Linux Windows
Policy path based rules file based rules access control list (ACL)
Timing dynamic subset of paths file based static ruleset persistent ACLs
TCP localhost proxy ports loopback proxy ports unsupported
Unix sockets allowlist allowlist via seccomp broker unsupported

Windows uses an AppContainer. The backend grants the generated AppContainer SID access to the lowered read and write roots, so Windows policies must use explicit read allowlists. Fine-grained TCP and Unix socket policies are rejected until Windows enforcement exists.

Network Policy

Sandbox mode denies direct network access by default. Proxy ports, local binding, and Unix sockets can be allowed with the Anthropic Sandbox Runtime network fields.

For a filesystem-only sandbox with unrestricted direct network access, set:

{
  "network": {
    "allowNetwork": true
  }
}

On Linux and macOS, allowNetwork disables landstrip network enforcement while leaving filesystem policy enforcement in place. Windows rejects unrestricted network policies until Windows network support exists.

Licensing

landstrip is licensed under LGPL-2.1-or-later.