---
description: Stay in the Cursor sandbox for cargo. Do not request all when sccache fails.
alwaysApply: true
---

# Cargo stays in the sandbox

`enableSharedBuildCache` remaps Cargo dirs. It does not cover sccache.
`~/.cargo/config.toml` sets `rustc-wrapper = "sccache"`. sccache is a
daemon (AF_UNIX / 127.0.0.1). Seatbelt denies both. That is
`sccache: error: Operation not permitted`.

`.cargo/sccache-wrapper` skips sccache when `CURSOR_SANDBOX` is set.
`.cargo/config.toml` overrides the home wrapper. Do not pin
`target-dir` / `build-dir`. That fights the shared Cargo cache.

Do **not** request `all` or disable the sandbox because `cargo` /
`clippy` / `rustc` failed. Do not retry as `RUSTC_WRAPPER=`. Restore
the wrapper if it is missing.

`all` is only for work that truly needs unrestricted filesystem or
network. A compile or unit test is not that.