SHOPIFY MIGRATION & CUSTOM APPS

Highlights

• Led the comprehensive migration of legacy e-commerce systems to the Shopify platform for enterprise clients in Japan. Engineered a robust integration layer to seamlessly synchronize legacy inventory logic, fulfillment pipelines, and customer data with the new architecture.
• Tackled severe technical debt: Took over a highly coupled, unmaintainable backend built on Odoo addons. Made the critical decision to rewrite the core logic from scratch within 2 weeks (replacing 2 months of failed patchwork by the predecessor), resulting in a clean, highly maintainable codebase.
• Transitioned the entire API integration from Shopify REST to GraphQL. Re-engineered complex legacy workflows, including migrating to Shopify email authentication, purchasing flows, voucher applications, and dynamic member-tier discounts utilizing Draft Orders and Metafields.
• Resolved previous security vulnerabilities by architecting a highly secure authentication layer. Built an App Proxy utilizing Shopify Polaris for front-channel authentication, ensuring the core backend remains strictly private and interacts solely via Server-to-Server auto-generated API Keys.
• Developed custom Storefront Extensions following Shopify’s latest specifications to enhance UI components for Profile and Order pages, successfully onboarding a traditionally conservative client base onto a modernized ecosystem.
• Business Impact: The architectural overhaul and performance improvements resulted in a 50% month-over-month surge in order volume for the initial store. This success directly secured 2 additional migration projects from the same client, leading to the ongoing management of 3 independent, highly optimized codebases tailored to each store's unique operations.