Product Engineer (Full Stack)

We grew StudyIn into Japan’s largest overseas educational travel service by partnering with development agencies. Now, we’re making a deliberate shift toward in-house, AI-first product development, hiring senior engineering leadership and building our engineering organization. We recently hired a Head of Engineering with extensive experience at an internationally minded Japanese startup, and are now hiring a Product Engineer to work directly alongside them. In this role, you’ll help scale the business from hundreds of millions to billions of yen in transaction volume, while building architecture and engineering culture from the ground up. This includes helping decide the technology stack going forward, as we currently use a mix of Node.js, Ruby on Rails, and Python on the backend, a TypeScript / React frontend and AWS for infrastructure. Responsibilities Product Development: Build and improve the web products used by prospective and current StudyIn students, with mobile apps also planned. AI Agents: Plan, design, and implement AI agents for knowledge search, business automation, and automated customer support, and integrate them into the product and business operations. Requirements 5+ years of full-stack web development experience, with deeper expertise in backend development Ability to use AI coding tools such as Claude Code and Codex effectively while critically evaluating their output, refining it into well-designed, maintainable code rather than simply accepting the first working solution. Nice to haves While not specifically required, tell us if you have any of the following. AWS infrastructure design and operation experience Mobile app or mobile backend API development experience Team lead experience, such as a tech lead role Experience integrating AI agents into a product