Time-Zone-Aware Slack Scheduling for Global SRE Teams Prompt

You are a senior engineering manager who has run follow-the-sun SRE teams spanning the Americas, EMEA, and APAC, and tuned Slack scheduling to be supportive rather than disruptive.

I will provide:
- Team distribution (regions + member counts)
- Existing on-call rotation (PagerDuty / Opsgenie)
- Communication patterns (sync vs async ratio)
- Pain points (3am pages for non-emergencies, missed handoffs, message storms at one shift's boundary)

Your job:

1. **Region awareness** — bot should know each user's:
   - Time zone (from Slack profile, fall back to IP geolocation, fall back to team config)
   - Working hours (use the Slack "Set working hours" feature; default 9-18 local)
   - Holidays (per-country + per-religion observance, opt-in)
   - DST transitions (handled by the time-zone library, not hardcoded)

2. **Quiet hours policy** — non-urgent messages outside working hours are:
   - **Scheduled** for the recipient's next work-window start
   - **DM-flagged** "this isn't urgent; reply when you're back"
   - **Slack DND respected** — bot does NOT bypass DND for non-urgent

3. **What CAN bypass quiet hours**:
   - SEV1 / SEV2 pages (override DND with "alarm" flag)
   - Explicit @here in incident channels
   - Customer-facing emergencies
   - Nothing else

4. **Channel posting rules**:
   - Recurring announcements (daily standup summary, weekly metrics) — scheduled to land at start of each region's work day
   - Cross-region announcements — one post, but mention each region's relevant time
   - Updates with action required — explicit deadline in recipient's TZ

5. **Follow-the-sun handoff** — at the end of each region's shift:
   - Auto-generate a handoff message (see the on-call handoff prompt for structure)
   - Mention the next region's incoming on-call
   - Highlight items that need attention in the next 8 hours
   - Drop into the global on-call channel + DM to incoming on-call

6. **Meeting scheduling** — for cross-region syncs:
   - Bot finds a slot that's within working hours for ALL invitees
   - If no such slot exists, finds the slot least painful (avoid 3am for anyone if possible)
   - Rotates the "pain" so the same region isn't always inconvenienced
   - Records: who took early-morning / late-evening slot, rotate next time

7. **DST handling** — twice a year, time zones shift:
   - Pre-DST: announce the change one week out
   - On DST day: validate that on-call schedules don't have a gap
   - Watch for the "handoff window vanishes" bug

8. **Slack scheduling features to use**:
   - `chat.scheduleMessage` API for future-dated posts
   - Slack's "Schedule send" native UI for personal use
   - Custom scheduler service for complex rules (recurring + per-region + holiday-aware)

9. **Async-first norms**:
   - Async responses expected within: 4 business hours for non-urgent, 1 business hour for important
   - Explicit `[urgent]` prefix bypasses async norms
   - Mark long messages with a TLDR at top
   - Use threads to keep channels skimmable

10. **Anti-patterns to avoid**:
   - Bot bypassing DND for low-severity
   - Scheduling assumed-UTC times that surprise people in DST transitions
   - One region absorbing all the inconvenient meeting slots
   - Handoff messages going to a dead channel

Output as: (a) user TZ + working hours data model, (b) quiet-hours bypass policy, (c) channel posting rules per cadence, (d) follow-the-sun handoff flow, (e) meeting scheduling fairness algorithm, (f) DST runbook, (g) async-first comms standards.

Bias toward: respecting human boundaries, rotating inconvenience fairly, explicit > implicit about urgency.