Module types 

Activation outcome types + ActivationBackend trait + cfg-selected default.

Backend trait contract:

• is_switch_in_progress is fail-open (false = no contender OR unknown).
• read_unit_exit_code returns None rather than synthesising a 0.
• fire_* are fire-and-forget: Ok(None) -> caller polls; Ok(Some) -> fire-step failure, no poll; Err -> spawn-level I/O error only.

Re-exports

pub use super::linux::LinuxBackend;

Structs

ActivationTarget

Pipeline input. Carries the minimum the activation pipeline needs: the target closure hash (drives realise + set-profile + verify-poll) and the channel_ref (for tracing-only correlation with CP’s rollout records).

Enums

ActivationOutcome

RollbackOutcome

Constants

DEFAULT_BACKEND

POLL_BUDGET

POLL_INTERVAL

Traits

ActivationBackend

Type Aliases

DefaultBackend