| license | Apache-2.0 |
| name | data-migration-specialist |
| description | Large-scale data migrations with validation, rollback, and zero-downtime strategies. Activate on: data migration, database migration, zero-downtime migration, dual-write, backfill, cutover, data validation, schema migration. NOT for: schema evolution in streams (use schema-evolution-manager), API versioning (use api-versioning-backward-compatibility). |
| allowed-tools | Read,Write,Edit,Bash(npm:*,npx:*,python:*,psql:*,docker:*) |
| category | Data & Analytics |
| tags | ["data-migration","zero-downtime","validation","rollback","cutover"] |
| pairs-with | [{"skill":"database-connection-pool-manager","reason":"Migrations impact connection pooling during cutover"},{"skill":"data-quality-guardian","reason":"Post-migration validation requires quality checks"},{"skill":"schema-evolution-manager","reason":"Schema changes accompany data migrations"}] |
Data Migration Specialist
Plan and execute large-scale data migrations with zero-downtime strategies, comprehensive validation, and reliable rollback plans.
Activation Triggers
Activate on: "data migration", "database migration", "zero-downtime migration", "dual-write", "backfill", "cutover", "data validation", "schema migration", "platform migration", "cloud migration"
NOT for: Streaming schema evolution → schema-evolution-manager | API backward compatibility → api-versioning-backward-compatibility | Warehouse optimization → data-warehouse-optimizer
Quick Start
- Audit source data — profile row counts, data types, nulls, constraints, and edge cases
- Choose strategy — big bang (downtime), dual-write (zero-downtime), CDC-based (continuous sync)
- Build validation framework — row counts, checksums, spot checks, and business rule assertions
- Run rehearsal — execute full migration on staging with production-scale data
- Plan rollback — define rollback triggers, procedure, and maximum acceptable rollback window
Core Capabilities
| Domain | Technologies |
|---|
| Strategies | Dual-write, CDC-based, big bang, strangler fig |
| CDC Tools | Debezium, AWS DMS, GCP Datastream, pglogical |
| Validation | Great Expectations, custom checksums, row-count reconciliation |
| Schema | Flyway, Liquibase, Prisma Migrate, Alembic |
| Orchestration | Airflow, Temporal, custom migration scripts |
Architecture Patterns
Zero-Downtime Migration (Dual-Write)
Phase 1: Dual-Write (days/weeks)
──────────────────────────────────
App writes → Old DB (primary)
→ New DB (shadow, async)
Reads from: Old DB only
Phase 2: Shadow Read Validation
──────────────────────────────────
App writes → Old DB + New DB
Reads from: Old DB (primary)
New DB (shadow, compare results)
Phase 3: Cutover
──────────────────────────────────
App writes → New DB (primary)
→ Old DB (shadow, for rollback)
Reads from: New DB
Phase 4: Cleanup
──────────────────────────────────
App writes → New DB only
Remove old DB writes
Decommission old DB (after rollback window expires)
