Migration Runbook Builder

Migrations fail when teams improvise the middle: untested phases, fuzzy rollback rules, and "we'll figure it out during the cutover" optimism. This skill turns a migration request into a written, gated, executable-in-sequence runbook — what moves, in what order, how each phase is verified, and exactly when and how to roll back. This is a planning playbook only: it produces the plan, it does not execute the migration.

Produce a complete migration runbook for moving a system, dataset, or service from a current state to a target state with minimum downtime and maximum recoverability. The runbook is a document a team (or an agent) can follow step by step on execution day, with explicit verification gates between phases and pre-defined rollback triggers and procedures.

• Migrating a database schema, datastore, or data between environments

• Moving a service between hosts, regions, cloud providers, or frameworks

• Upgrading a major dependency, runtime, or platform version in production

• Decommissioning a legacy system that users or jobs still depend on

• Any change described as "we can't afford downtime" or "there's no easy undo"

• Planning test coverage for a new feature — use spec-to-test-plan instead. This skill covers migration execution planning (phases, gates, rollback), not feature test planning.

• Writing a code-review checklist — use review-checklist-builder.

• Handling an active outage or incident — use sev-decision-playbook.

• Debugging a crash — use stack-trace-translator.

• Verifying AI-generated output — use ai-output-quality-gate.

• You are already mid-migration without a plan: write the remaining runbook for what's left, but be honest in the output that phases already completed are unverifiable retroactively.