Available to hire
Hi, I’m Tatsuya Kuroda, a full stack Shopify app developer based in Tokyo, Japan. I build custom and public Shopify apps using Node.js, React, Shopify APIs, and secure backend architectures to deliver fast, reliable ecommerce automation and merchant-friendly experiences.
Over the years I have led end-to-end development of 20+ Shopify apps, built scalable backends with Node.js, Express, PostgreSQL, and MongoDB, and implemented optimizations that cut API calls and boosted uptime. I collaborate with merchants, PMs, and designers to ship features that boost revenue and streamline operations.
Skills
Language
Japanese
Fluent
English
Fluent
Work Experience
Senior Shopify App Developer
January 1, 2021 - November 17, 2025Led end-to-end development of 20+ custom and public Shopify apps, improving merchant automation, reporting visibility, and storefront functionality. Built scalable app backends using Node.js, Express, PostgreSQL, and MongoDB, achieving 32% faster API response times and a 40% reduction in server load. Developed advanced features including subscription engines, bundle logic, checkout UI extensions, admin extensions, and inventory automation workflows, helping clients reduce manual work by up to 65%. Implemented Shopify Admin API & GraphQL optimizations that decreased API call volume by 28%, lowering infrastructure costs for merchants. Upgraded multiple apps to Shopify App Bridge v3 and Shopify’s new OAuth flows, improving security and reducing auth-related failures by over 70%. Designed high-quality React/Remix frontends with Polaris, improving UX clarity and reducing merchant onboarding time by 40%. Integrated third-party services including Klaviyo, Recharge, ShipStation, and ERP/CRM
Full-Stack Developer
January 1, 2021 - January 1, 2021Built 30+ full-stack web applications using React, Next.js, Vue, Node.js, Express, and modern JavaScript/TypeScript. Architected secure REST and GraphQL APIs, achieving 25% faster query execution and improving system scalability for high-traffic SaaS platforms. Designed optimized database models in MongoDB and PostgreSQL, reducing query load by up to 40% and improving data accuracy for analytic dashboards. Developed authentication systems with JWT, OAuth, and role-based access control, decreasing unauthorized access issues by over 90%. Implemented CI/CD pipelines (GitHub Actions, GitLab CI), reducing deployment time from 15 minutes to under 3 minutes. Improved web performance through code splitting, caching, and image optimization, increasing Lighthouse performance scores by 30–45% on average. Built dashboards and internal tools that automated day-to-day business operations, reducing human error and saving teams 10+ hours/week. Managed integrations with Stripe, Firebase, AWS, Google
Education
Qualifications
Industry Experience
Software & Internet, Retail, Professional Services, Other
Skills
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