# Review by Principal Systems Engineer (Google/Stripe caliber) (Round 2)

## Principal Systems Engineer — Review Complete

VERDICT: **approve** ✅

FINDINGS:
- [src/colonyos/slack_queue.py]: Deferred 👀 for passive messages fires before queue item creation — if downstream fails, user sees 👀 with no follow-up. Pre-existing pattern for mentions; acceptable for v1.
- [src/colonyos/slack_queue.py]: `message` event binding receives `message_deleted` subtypes with no `text` field — safely handled by existing empty-text guard, but the resilience is implicit rather than explicit.

SYNTHESIS:
This is a well-scoped, minimal-blast-radius change that correctly activates a latent configuration path. The implementation touches exactly the right code paths with no unnecessary abstractions. From a systems reliability perspective, the key question is "what breaks at 3am?" and the answer is "nothing new" — all failure modes (queue full, triage errors, reaction failures, dedup races) are handled by existing infrastructure, and the new code correctly routes passive messages through those same paths. The conditional 👀 reaction is the most operationally important detail (silent monitoring without creepy UX), and it's implemented with the right two-phase pattern: suppress at intake, add after triage. The `is_passive` flag flows cleanly through the system without polluting the queue item schema. Test coverage is comprehensive with 680 new lines covering dedup races, end-to-end flows, and edge cases. The only thing I'd want for v2 is explicit `message_subtype` filtering in `_handle_event` rather than relying on downstream guards, but that's defense-in-depth, not a correctness issue. All 318 tests pass. Ship it.

Review artifact written to `cOS_reviews/reviews/principal_systems_engineer_google_stripe_caliber/20260401_142500_round1_you_are_a_code_assistant_working_on_behalf_of_the_engineering_team_the_following.md`.