Available to hire
I am a Senior Full-Stack Engineer based in Tokyo with 8+ years of experience building secure, scalable platforms across FinTech, HR-Tech, and AI-driven digital transformation. I design end-to-end systems using React, Next.js, Node.js, NestJS, and AWS to support high-volume transactions and automation workflows.
I have delivered payments systems, workflow automation tools, and marketplace features used by 100K+ users. I work well in Agile delivery, microservices modernization, and regulatory compliance (GDPR, KYC). I communicate effectively with cross-border product, AI, and design teams to ship reliable features quickly.
Skills
Language
English
Fluent
Work Experience
Senior Full-Stack Engineer at Quest
September 1, 2025 - September 1, 2025Led feature development for Quest Marketplace Platform using Next.js, React, Node.js, and Tailwind CSS, supporting 100K+ monthly users. Designed growth-ready backend services on AWS ECS, RDS, and S3 to improve city-wide Booking & Scheduling reliability, reducing booking failures by 18% during peak demand. Built secure Payments & Wallet experiences with Stripe, refining API design and checkout flows that increased order completion rates by 22% and reduced abandoned payments. Improved mobile + web performance with SSR/ISR strategies, boosting SEO visibility. Introduced GraphQL to reduce over-fetching and simplify data integrations across frontend clients and partner teams. Improved deployment confidence via GitHub Actions and TypeScript-based quality controls. Collaborated with product managers, designers, and engineers across Japan and Singapore in a remote-first culture.
Mid-Level Full-Stack Engineer at Exawizards
July 1, 2022 - July 1, 2022Designed and delivered automation features across ExaPlatform and ExaCare using React + TypeScript to streamline healthcare workflows and reduce manual entry for clinical staff by up to 50%, ensuring faster patient handling. Architected secure NestJS microservices on AWS (Lambda, API Gateway, DynamoDB), enabling faster and compliant data exchange between healthcare systems and DX platforms. Improved enterprise HR operations on ExaHR by developing GraphQL APIs and Node.js services that reduced repetitive reporting tasks for HR admins by 60%. Evolved legacy services into microservices with DDD principles, increasing system stability while improving deployment frequency and scalability. Standardized infrastructure provisioning with Terraform and AWS ECS, improving onboarding for new services and development environments. Enhanced operational reliability by enabling distributed tracing, CloudWatch alarms, and log indexing to reduce incident resolution time. Collaborated with AI researchers
Junior Full-Stack Developer at Givery
July 1, 2019 - July 1, 2019Improved the Developer Assessment Platform by developing candidate test flows using React + TypeScript and securing submission services with Node.js, Express, and PostgreSQL, helping hiring teams shorten review cycles by 35% and cut manual score checks. Enhanced the Recruiter Dashboard by optimizing API performance and adding Vue-based UI improvements, giving HR teams faster access to scoring insights and reducing average result loading times by 40%. Strengthened the Candidate Management System using secure file handling and data validation, supporting reliable assessment storage under compliance guidelines. Supported release stability by integrating CI pipelines with GitLab CI, automated testing, and Docker-based environments for consistent deployments. Participated in iterative UX improvements using design feedback, Jira task coordination, and collaborative code reviews with senior engineers.
Education
Bachelor of Computer Science at University of Aizu
January 1, 2013 - March 1, 2017Qualifications
Industry Experience
Software & Internet, Financial Services, Professional Services
Skills
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