This PR introduces `fabro-beastie`, a new cross-platform idle sleep
prevention crate (named after Beastie Boys — *No Sleep Till Brooklyn*),
and wires it into `fabro-cli` behind an opt-in `sleep_inhibitor` Cargo
feature. Long-running `fabro run` and `fabro exec` commands can be
killed by OS idle sleep, so when the feature is compiled in and
`prevent_idle_sleep = true` is set in `cli.toml`, an RAII guard keeps
the system awake for the duration of the command.
The `fabro-beastie` crate provides platform-specific backends: on macOS
it uses IOKit power assertions (`PreventUserIdleSystemSleep`), on Linux
it spawns `systemd-inhibit` (with `gnome-session-inhibit` as fallback)
and sets `PR_SET_PDEATHSIG` to prevent orphaned processes. Both fall
back to a no-op dummy backend if the platform backend is unavailable.
The public API is a single `guard(bool)` function returning an
`Option<SleepInhibitorGuard>` that releases on drop.
On the integration side, a `prevent_idle_sleep` boolean field is added
to `CliConfig` (defaulting to `false`), and `cfg`-guarded sleep guards
are placed at the entry points of both the `exec` and `run` command
paths in `fabro-cli`. Since the feature is off by default, there is zero
impact on normal builds — `fabro-beastie` is only pulled in when
explicitly enabled via `--features fabro-cli/sleep_inhibitor`.
### Fabro Details
<details>
<summary>Ran 7 stages in 20m 33s for $3.24</summary>
| Stage | Duration | Cost | Retries |
|---|---|---|---|
| start | 0s | – | 0 |
| toolchain | 0s | – | 0 |
| preflight_compile | 0s | – | 0 |
| preflight_lint | 0s | – | 0 |
| implement | 0s | $1.26 | 1 |
| simplify | 0s | $1.98 | 0 |
| verify | 0s | – | 0 |
| **Total** | **20m 33s** | **$3.24** | **1** |
</details>
<details>
<summary>Ran <code>ImplementAndSimplify.fabro</code> (10 nodes and 13
edges)</summary>
```dot
digraph ImplementAndSimplify {
graph [
goal="Implement and simplify",
model_stylesheet="
* { backend: api; model: claude-opus-4-6;}
"
]
rankdir=LR
start [shape=Mdiamond, label="Start"]
exit [shape=Msquare, label="Exit"]
toolchain [label="Toolchain", shape=parallelogram, script="command -v cargo >/dev/null || { curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y && sudo ln -sf $HOME/.cargo/bin/* /usr/local/bin/; }; cargo --version 2>&1", max_retries=0]
preflight_compile [label="Preflight Compile", shape=parallelogram, script="cargo check 2>&1", max_retries=0]
preflight_lint [label="Preflight Lint", shape=parallelogram, script="cargo clippy -- -D warnings 2>&1", max_retries=0]
fix_lints [label="Fix Lints", prompt="The preflight lint step failed. Read the build output from context and fix all clippy lint warnings.", max_visits=3]
implement [label="Implement", prompt="Read the plan file referenced in the goal and implement every step. Make all the code changes described in the plan."]
simplify [label="Simplify", prompt="@prompts/simplify.md"]
verify [label="Verify", shape=parallelogram, script="cargo clippy -- -D warnings 2>&1 && cargo test 2>&1", goal_gate=true, retry_target="fixup"]
fixup [label="Fixup", prompt="The verify step failed. Read the build output from context and fix all clippy lint warnings and test failures.", max_visits=3]
start -> toolchain
toolchain -> preflight_compile [condition="outcome=success"]
toolchain -> exit
preflight_compile -> preflight_lint [condition="outcome=success"]
preflight_compile -> exit
preflight_lint -> implement [condition="outcome=success"]
preflight_lint -> fix_lints
fix_lints -> preflight_lint
implement -> simplify -> verify
verify -> exit [condition="outcome=success"]
verify -> fixup
fixup -> verify
}
```
</details>
⚒️ Generated with [Fabro](https://fabro.sh)
---------
Co-authored-by: Fabro <noreply@fabro.sh>
Pre-generates a ULID in the parent, passes it to the child via hidden
`--run-id` arg, prints the ULID to stdout, and exits immediately.
Child stdout/stderr go to `{run_dir}/detach.log`. Uses `setsid()` on
unix to detach from the controlling terminal. Existing `fabro ps` and
`fabro logs` work with no changes since `run.pid` and `conclusion.json`
are written by the child as usual.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
fabro-util is a low-level crate depended on by almost everything, so its
build.rs reruns cascaded through the whole workspace. fabro-cli is the
leaf binary — nothing depends on it, so rebuilds are limited to just
that one crate.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
