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E-commerce / Retail · 2024
Order and inventory microservices for a major Japanese e-commerce platform
Migrated a monolithic order/inventory system to Go-based microservices in phases. 3.5× peak throughput and zero incidents during seasonal sales.
Anonymized at the client’s request.
Challenge
- The legacy order/inventory monolith had become a bottleneck for both feature delivery and scaling during sales.
- The internal team needed to stay focused on new product features and was looking for additional capacity to drive the microservices split.
- The work required strong design discipline to extract services in phases without taking down production.
Approach
- Lab-style team: 1 Bridge SE, 6 backend engineers, 1 SRE, 1 QA.
- Strangler-fig migration pattern to peel services off the monolith one domain at a time.
- Kafka-based event-driven architecture to keep order, inventory, and fulfillment loosely coupled.
- Datadog + SLO-driven monitoring from day one, with release decisions tied to error budgets.
Results
- ~3.5× peak order throughput.
- Zero incidents during the most recent year-end sales window.
- New-feature lead time reduced from 2 weeks to 3 days.
- Runbooks and SLO design handed off to the internal SRE team, which continues to own production.
Client voice
「Splitting a monolith is high-risk work, but the Bridge SE's careful capture of every requirement nuance kept us on the original plan.」