# Migrate Customer Data

> Migrate customer data so meaning, ownership, access, and history survive. Use when acceptance is preserved semantics, not row-count equality. Do not use for the authority switch of a live writer.

- Skill: `sylphxai/migrate-customer-data` (Agent Skill, multi-file: 3 files)
- Install (CLI): `npx skillmds@latest add sylphxai/migrate-customer-data`
- Raw SKILL.md: https://api.skillmd.com/api/skills/sylphxai/migrate-customer-data/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: SylphxAI (https://skillmd.com/u/sylphxai)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/sylphxai/migrate-customer-data

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# Migrate Customer Data

Row-count equality is weak proof. Meaning, access, and history have to survive. A migrated row the owner can no longer find, export, or delete is a failed migration.

Open [migration contract and mapping](references/migration-contract-and-mapping.md) and [rehearsal and cutover](references/rehearsal-cutover-and-acceptance.md) when the mapping or rehearsal needs depth.

Use `execute-hard-cutover` for the live writer switch.