Open to opportunities

Hiroyuki Josey Sekine

@hiroyukijoseysekine

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Fullstack/Frontend Developer with expertise in web applications.

Japan

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What I'm looking for

I am looking for a collaborative environment that values innovation and offers opportunities for growth.

I am a Fullstack/Frontend Developer with a strong background in building production-ready web applications using Next.js, TypeScript, and Ruby on Rails. My experience includes delivering features across both UI and backend, focusing on usability, performance, and maintainability. I have successfully integrated APIs and developed automation tools using OpenAI and AWS Lambda, enhancing internal workflows with Notion and GitHub Actions.

Throughout my career, I have demonstrated my ability to contribute effectively in Agile teams. My recent projects include streamlining workflows and improving code readability by implementing Notion for documentation and project management. I have also developed secure integrations for banking functionalities and built user-friendly interfaces for transaction history views, showcasing my commitment to delivering high-quality software solutions.

Experience

Work history, roles, and key accomplishments

Fullstack Developer

Meefi

Jan 2025 - Mar 2025 (2 months)

Streamlined workflows by introducing Notion for documentation and project management, improving overall efficiency and code readability. Implemented functionality for users to view unpaid billing information and developed secure integration for bank account linking and credit card information registration. Built UI to display transaction history based on registered bank data.

Ruby on Rails Next.js PostgreSQL Notion UI API Integration

Frontend Developer

PKSHA Technology

Jan 2025 - Mar 2025 (2 months)

Joined the development team for an application generating chat records from call center conversations. Led frontend development and built the product's Webhook system, handling API integration, UI implementation, and comprehensive testing. Identified and collaborated to resolve several backend issues, contributing to overall system stability and quality.

Next.js Docker Webhooks API Integration UI Testing Collaboration

Software Developer

PKSHA Technology

Jul 2024 - Aug 2024 (1 month)

Developed an automated GitHub PR description generator using OpenAI and implemented a system with GitHub Actions, AWS Lambda, and Bedrock for PR description generation. Enhanced descriptions by integrating Notion API to incorporate relevant task details, providing more context and sophistication. Improved UI for streamlined code review processes with intuitive update and regeneration features.

Python LLM AWS Lambda GitHub Actions Bedrock Notion UI

Frontend Developer

GACCI

Jun 2023 - Jun 2024 (1 year)

Developed new features by integrating API data and enhanced the user interface by building a search engine, managing data with Redux. Upgraded the Excel file processing system to support additional cities, enabling customer acquisition from various regions. Utilized Sass/SCSS and third-party libraries like Axios to create responsive, cross-browser compatible, and optimized web applications.

Next.js Redux SCSS Axios Webpack ESLint API Integration UI Development

Fullstack Developer

KotobaFlow

Developed and contributed to both backend (Ruby on Rails) customization and frontend (React) design and implementation. Focused on usability and maintainability to deliver a robust personal application.

Ruby on Rails React Backend Development Frontend Development

Education

Degrees, certifications, and relevant coursework

Rishho University

Bachelor of Law, Law

Studied fundamental legal principles, including civil law, criminal law, and constitutional law. Gained a comprehensive understanding of the Japanese legal system and its applications.

Le Wagon

Certificate in Web Development, Web Development

Completed a 10-week intensive web development course, mastering full-stack development with Ruby on Rails and JavaScript. Developed practical skills in building web applications, including database management and front-end frameworks.