Migrate a global event streaming platform

---
name: migrate-a-global-event-streaming-platform
category: code
description: Migrate a global event-streaming platform through event identity, schema and ordering parity, security, regional authority, consumer offsets, cutover, rollback, and reconciliation. Use when critical streams must move without duplicate effects or silent loss.
---

# migrate-a-global-event-streaming-platform

Preserve the authoritative outcome of every event across regions and platforms.

## When to use

- Use for broker replacement, managed-service move, regional redesign, acquisition, or protocol change.
- Activate qualified platform, application, data, security, privacy, network, finance, reliability, vendor, and regional authority.

## Preconditions

- Inventory producers, consumers, topics, partitions, keys, schemas, transactions, offsets, retention, replay, dead letters, regions, residency, service levels, and business effects.
- Define canonical event identity, operation identity, source-of-truth outcomes, recovery objectives, and stop authority.
- Preserve an independent rollback path and enough capacity for overlap plus recovery.

## Procedure

Complete **stream and dependency inventory**, **semantic and security parity**, **regional migration and authority transfer**, and **rollback and retirement**.

1. Build a **global streaming migration register** for event type, producer, consumer, topic, partition key, schema, ordering, identity, side effect, region, retention, security, owner, and criticality.
2. Compare delivery, ordering, transactions, compaction, timestamps, offsets, acknowledgement, retry, dead-letter, quotas, encryption, identity, authorization, audit, and failure semantics.
3. Assign canonical event and operation IDs plus source revision, schema, region, occurred time, accepted time, and authority epoch.
4. Update producers and consumers to tolerate overlap, deduplicate operations durably, reject stale epochs, and preserve required ordering.
5. Establish controlled source capture or fan-out with immutable audit, per-partition watermarks, hashes, and no second side-effect authority.
6. Build partition and transaction lineage for source and target topic, partition, offset, stable key, partitioner version, transaction or operation ID, and commit or abort marker.
7. Define cutover as a source-offset vector plus committed-transaction frontier; buffer live events by key until that key’s historical replay completes and apply transactions only after all required members plus the commit marker exist.
8. Transfer authority by stable key range or transaction group when topology differs.
9. Reconcile historical transfer and live delta by event identity, sequence, partition, schema, tombstone, transaction, retention, and business outcome.
10. Test privacy, residency, key management, access, isolation, audit, vendor control, and emergency authority in every region.
11. Migrate representative topics and consumers, including partition-count and hash change, multi-topic transaction, late historical event, compacted tombstone, region failure, and poison cases.
12. Transfer authority by producer, topic, stable key or transaction group, consumer, and side effect only after frontiers, readiness, and external acknowledgements converge.
13. Fence legacy producers and consumers through epochs; record queued, accepted, retried, dead-lettered, canceled, and applied operations.
14. Monitor lag, ordering, duplicates, loss, schema failures, retries, saturation, latency, business invariants, and regional failure.
15. Rehearse rollback after target-accepted events, downstream side effects, schema change, regional partition, and consumer offset advance without replaying acknowledged action.
16. Retire legacy only after retained history, replay, audit, legal hold, credentials, network, billing, support, and restore duties are proven.

## Failure plan

- If event outcome is ambiguous, stop the affected authority transfer and reconcile before replay.
- If deduplication or stale-epoch rejection is not durable, do not dual-run side-effecting consumers.
- If a region cannot meet security or residency obligations, keep it on the governed legacy path.
- If rollback would replay accepted effects, preserve the target outcome ledger and reconcile forward.

## Worked example

A global marketplace moves orders, payments, inventory, identity, notifications, and analytics streams between platforms while producers and consumers span regions, transactions and ordering differ, historical replay is incomplete, and both brokers must overlap. The migration assigns canonical identities, tracks partition watermarks, fences side effects, reconciles business outcomes, and rehearses rollback after target-accepted payments.

## Done

- A global streaming migration register verifies producers, consumers, identities, schemas, keys, ordering, regions, security, retention, side effects, and ownership
- An event, offset, schema, transaction, security, and business-outcome parity report proves complete transfer, deduplication, stale-epoch rejection, regional obligations, and unresolved exceptions
- A cutover and rollback rehearsal demonstrates source-offset vectors, committed-transaction frontiers, key-order preservation across history and live traffic, unsplit transactions, per-stream authority, external acknowledgements, accepted-effect preservation, partition recovery, and legacy restoration