Artifact: Title + TL;DR — Historical Notification Backfill
Historical-notification-backfill design note, with title and TL;DR first -- exercises co-01 and co-03.
Raw document text, as the author would ship it:
# Backfill Historical Shipment Notifications
**TL;DR**: send a one-time, opt-out backfill SMS to the ~1,200 customers affected by last month's
notification-delivery bug, informing them their shipment already arrived. Shipping Thursday, pending
legal's sign-off on the message copy.
## Background
Last month's bug silently dropped the "shipped" notification for a subset of orders placed between
March 3-March 9, before the fix landed. Support tickets since then show these customers had no
visibility into their shipment status until it simply arrived.Last updated July 15, 2026