Full-Stack · Game · QA Engineer
Takeshi Juan
Engineering products with precision. From AAA game studios to AI-powered platforms. Currently building the future of generative AI and predictive intelligence in Tokyo.
I craft software that bridges technical excellence with exceptional user experience—from AAA game engines to production-grade AI systems.
After graduating from a university in Taiwan in 2017, I began my career at X-LEGEND Entertainment developing smartphone MMORPGs. I then completed my Master's in Information Science and Engineering at Tokyo Institute of Technology.
At Marvelous, I developed the arcade rhythm game "WACCA" using Unreal Engine 4, focusing on game UI implementation and server communication systems.
My time at Square Enix involved building internal QA automation systems for major titles including FF7 Rebirth and Dragon Quest series, integrating with UE4/5 and Python backend systems.
Currently at Kyuzan, I lead a 6-member client engineering team for a new NFT mobile game, driving technical decisions from architecture design to CI/CD pipeline construction.
Clean Architecture
Domain-driven design with clear separation of concerns for maintainable, scalable codebases.
AI-Augmented Development
Leveraging Claude Code, Warp, and Windsurf to maximize team output and code quality.
Craftsmanship
Obsessive attention to detail, from pixel-perfect UI to optimized system performance.
Hengen Studio
Generative AI Platform
A modern image transformation service using the latest Generative AI APIs. Focus on visual intelligence, fast pipelines, and production-grade AI integration.
Founder & Full-Stack Engineer
SUIJIN AI
Predictive Analytics Platform
An AI-powered boat-race result prediction and analysis service. Leverages BoatraceOpenAPI for real-time data, GPT-4 via Vercel AI Gateway for race analysis, and Supabase for data persistence with PayPay payment integration.
Founder & Full-Stack Engineer
NFT Mobile Game
Kyuzan Inc.
Leading a 6-member client engineering team for a new blockchain mobile game. Clean Architecture with Unity and NestJS backend, full CI/CD automation with GitHub Actions.
Client Engineering Lead
QA Automation System
Square Enix
Internal automated QA system for major titles including FF7 Rebirth and Dragon Quest series. UE4/5 integration with Python server-side development.
QA Engineer
WACCA
Marvelous Inc.
Arcade rhythm game development using UE4/C++. Responsible for game UI implementation, server communication features, and extensive codebase refactoring.
Game Engineer
Real Estate Platform
Ielove Group
Web platform development for real estate industry. Full-stack development from frontend to database design, including internal shared library development.
Web Engineer
Aura Kingdom Mobile
X-LEGEND Entertainment
MMORPG development for smartphone platforms using CRYENGINE. Implemented login bonuses, mount systems, awakening systems, and guild content.
Game Engineer
Languages
Game Engines
Frontend & Frameworks
Backend & Frameworks
Cloud & Infrastructure
Databases
Payments & APIs
Testing
AI & Productivity
Hengen Studio
Tokyo, JapanFounder & Full-Stack Engineer
Modern image transformation service using Generative AI APIs. Visual intelligence and production-grade AI integration.
SUIJIN AI
Tokyo, JapanFounder & Full-Stack Engineer
AI-powered boat-race prediction and analysis platform. Next.js 16, Supabase, Vercel AI SDK, PayPay integration.
Kyuzan Inc.
Tokyo, JapanClient Engineering Lead
Leading 6-member Unity team for new NFT mobile game. Technical architecture, CI/CD, team management.
Square Enix
Tokyo, JapanQA Engineer
Internal QA automation for FF7 Rebirth, Dragon Quest. UE4/5 integration, Python backend.
Marvelous Inc.
Tokyo, JapanGame Engineer
WACCA arcade rhythm game. UE4/C++ development, UI systems, server communication.
Ielove Group
Tokyo, JapanWeb Engineer
Real estate web platform. Full-stack PHP development, internal library design.
Part-time during graduate studies
Tokyo Institute of Technology
Tokyo, JapanMaster's Student
Information Science and Engineering. Advanced research in computer science.
X-LEGEND Entertainment
TaiwanGame Engineer
Aura Kingdom mobile MMORPG. CRYENGINE/C++ development, gameplay systems.
Let's build something together.
Whether you have a project in mind, need technical consultation, or just want to connect — I'm always open to new conversations.
Location
Tokyo, Japan
Availability
August 2025
Working Style
Remote Preferred