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

## Principal Systems Engineer Review — Complete

**VERDICT: approve** ✅

### FR Coverage: 8/8 complete, no TODOs or placeholders

### Key Findings

| Finding | Severity | Action |
|---------|----------|--------|
| Rate-limit warning leaks to passive messages (lines 194-204, `slack_queue.py`) — posts `:warning:` to channel even for passive msgs, violating "invisible until relevant" goal | Non-blocking | Defer to v2 |
| Post-triage 👀 fires before queue item creation | Non-blocking | Pre-existing pattern, not a regression |
| No explicit `message_subtype` filtering on `message` events | Non-blocking | Downstream `should_process_message()` handles this |

### What makes this solid

1. **~45 lines of production code** activating existing infrastructure — dedup, triage, filters all reused unchanged
2. **Security chokepoint preserved** — `should_process_message()` untouched, all 5 filters apply uniformly
3. **`is_passive` flag** is clean metadata computed once, consumed at exactly 2 decision points
4. **2954 tests pass**, 35 new tests covering dedup races, dual-event delivery, queue-full suppression, startup warnings

### SYNTHESIS
This is a well-executed systems change. The only gap — rate-limit warnings leaking to passive messages — is low-impact (rate limits rarely hit, message goes to thread not main channel). The 10:1 test-to-code ratio and minimal blast radius make this safe to ship.

Review artifact written to `cOS_reviews/reviews/principal_systems_engineer_google_stripe_caliber/20260401_143500_round1_you_are_a_code_assistant_working_on_behalf_of_the_engineering_team_the_following.md`.