About Me

A passionate developer with over 10 years of experience building digital products that make a difference

Hi, I'm Yoshiki

I'm a Full Stack Developer and Solution Architect based in Tokyo, Japan. With over a decade of experience in software development, I specialize in building high-performance web applications that scale.

My journey in tech started with a curiosity about how things work on the internet. Today, I help businesses transform their ideas into robust digital solutions, focusing on clean architecture, performance optimization, and exceptional user experiences.

When I'm not coding, you'll find me exploring new technologies, contributing to open-source projects, or sharing knowledge through tech blogs and community events.

Skills & Expertise

A comprehensive overview of my technical skills and proficiency levels

Backend

TypeScript 96%

Java (8, 11) 95%

Spring Boot 90%

Ruby/Rails 85%

Golang 80%

Kotlin 75%

Frontend

TypeScript 90%

React/Next.js 90%

Vue.js 85%

Three.js 75%

Database & Infrastructure

MySQL 90%

PostgreSQL 85%

Redis 80%

Docker 85%

Kubernetes 80%

Cloud & DevOps

AWS (EC2, CDK) 85%

GitHub Actions 90%

GitLab CI 85%

OpenAPI 80%

Flyway 75%

Professional Journey

A glimpse into my career progression and key achievements

Backend Engineer

2023 - Present

ヤフー株式会社

Yahoo!ショッピングの配送機能開発。3000req/秒を処理する高負荷システムの設計・実装

Backend Engineer

2021 - 2022

楽天グループ株式会社

ラクマアプリの新配送機能開発。パフォーマンス最適化により応答時間を50%改善

Full Stack Engineer

2019 - 2021

フリーランス

DCM、OPTiM、GMOなど複数企業のプロジェクトに参画。ECサイトから医療ロボットまで幅広く開発

What Drives Me

Core values that guide my work and collaboration

Clean Code

Writing maintainable, scalable code that stands the test of time

Collaboration

Building strong relationships with clients and team members

Innovation

Staying current with technology to deliver cutting-edge solutions