Migration Pattern — Checklist

Pattern: Migration
Component: checklist.md
Version: 1.1 | Updated: 2026-07-16

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Gate: No cutover without green recon; no contract without soak evidence + human approval.

Design

• Source and target states explicit
• Consumer inventory complete with owners
• Expand → dual/shadow → cutover → contract sequenced
• Rollback defined per reversible phase
• Point of no return named
• Observability signals and thresholds set

Before cutover

• Expand deployed and verified
• Dual/shadow running
• Reconciliation queries green
• Backup/restore rehearsed if High risk
• Named cutover approver recorded

After cutover

• Soak within SLO
• Contract only after soak evidence file
• Audit pack (gates + recon + approvers) stored with ticket