Project Overview
A high-throughput logistics automation microservice engineered for high-volume Shopify merchants handling thousands of orders across multiple third-party logistics (3PL) fulfillment centers.
Key Challenges & Objectives
Manual shipping label generation and multi-warehouse order routing caused fulfillment bottlenecks during peak holiday sales. The client required a low-latency automation engine to process orders in seconds.
Architecture & Implementation
Built with Dockerized Node.js and Express microservices, Shopify Webhook listeners, Redis BullMQ background queue processing, and direct multi-carrier API integrations (DHL, FedEx, UPS, Royal Mail).
Core Features & Deliverables
- Intelligent Carrier Rate Selection: Algorithmic rate comparison selecting the fastest and most cost-effective carrier based on weight, dimensions, and destination.
- Automated Thermal Label Streaming: Instant generation and network streaming of ZPL shipping labels directly to warehouse thermal printers.
- Real-Time Fulfillment Webhooks: Immediate synchronization of package tracking numbers and fulfillment statuses back to Shopify customer accounts.
- Address Correction & Validation: Automated postal address normalization catching invalid zip codes before courier submission.
Business Impact & Results
Reduced per-package label generation time from 2 minutes down to 1.2 seconds, effortlessly processing over 50,000+ orders during Black Friday without a single timeout.
