Core summary (answer-first): Migrating a massive e-commerce monolith like Magento 2 to a distributed Microservices architecture requires a zero-downtime cutover technique. The only viable strategy in production is a 3-phase Strangler Fig pattern:
Phase 1 (Read-Path Strangling): Use Envoy API Gateway to route all read traffic (Catalog/Search) to a new cluster of Go Microservices, while data is synchronized in real time from Magento’s MySQL to PostgreSQL/OpenSearch via Debezium CDC (Change Data Capture) on the binlog. Phase 2 (Write-Path & Bidirectional Sync): Extract the core write domains (Cart, Order, Customer) into independent Microservices, implementing two-way synchronization back to Magento through a Transactional Outbox Worker built with Go 1.24 and Apache Kafka to maintain backward compatibility with legacy subsystems (ERP, WMS, Fulfillment). Phase 3 (Cutover & 30-Day Hot Standby): Cut over 100% of traffic to the Microservices, keep Magento running as a hot standby replica for 30 days with a rollback capability of under 5 minutes, and only then decommission the physical/EC2 servers. 1. The “Big Bang Rewrite” Trap and the Harsh Reality of the Magento Monolith When a Magento 2 e-commerce system reaches millions of SKUs and processes tens of thousands of orders per day during Mega Sale campaigns, the engineering team routinely faces familiar nightmares:
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