# Review by Principal Systems Engineer (Google/Stripe caliber) (Round 3)

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## Review Complete — Principal Systems Engineer (Google/Stripe caliber)

**Branch:** `colonyos/recovery-7cc0851d44`

VERDICT: **approve** ✅

FINDINGS:
- **[src/colonyos/daemon/_watchdog.py]**: The `_get_daemon_module()` lazy import pattern correctly solves the module-namespace patching problem. At 3am when a watchdog stall fires, `mod.request_active_phase_cancel()` resolves through the daemon package namespace — exactly where `unittest.mock.patch` substitutions land. Looks wrong, is precisely correct.
- **[src/colonyos/daemon/_resilience.py]**: Lazy imports inside method bodies (`from colonyos.recovery import ...`) break circular dependencies at negligible cost (Python caches `sys.modules`). Right trade-off for package structure.
- **[src/colonyos/daemon/_helpers.py]**: Beyond PRD scope (4 submodules vs 3 specified). Justified — 7 pure-ish methods with read-only `self.*` access, low-risk extraction done while already touching the file.
- **[src/colonyos/daemon/__init__.py]**: MRO `Daemon → _WatchdogMixin → _ResilienceMixin → _HelpersMixin → object` — linear, no diamond, no `__init__` in mixins. Re-exports at lines 58-61 preserve backward compatibility.
- **[src/colonyos/daemon/_ui.py]**: Clean extraction of 3 standalone classes with zero Daemon coupling. Lowest-risk targets, correctly done first.

SYNTHESIS:
From a systems reliability perspective, this refactoring is operationally invisible — and that's exactly what you want. The daemon's runtime behavior, failure modes, and observability surface are completely unchanged. The watchdog still fires on stall, recovery still preserves dirty worktrees, the circuit breaker still trips on systemic failures. The blast radius is zero: 149 tests exercise every code path and would catch any import-time regression. The 6 sequential, independently revertable commits mean you can `git bisect` to any specific extraction. The 3 `TestDailyThreadLifecycle` failures are confirmed pre-existing on `main`. This is the boring, correct refactoring that was needed after 6 failed attempts at cleverness. Ship it.

Review artifact written to `cOS_reviews/reviews/principal_systems_engineer/20260402_review_daemon_package_refactor_recovery.md`.
