Product Lead Engineer, HR & Payroll

This role leads product development for freee HR and Payroll, a large core platform supporting tens of thousands of companies. The product is undergoing a shift from a service used by people to a service used by AI, with a large repository and user base. The engineer is expected to lead development practices that use AI agents as part of the engineering process.

Responsibilities include selecting product specifications and designing and implementing scalable architecture. The role also incorporates current LLM and AI-agent tools, including Claude Code, into development to improve individual and team productivity. The engineer works with product managers, designers, and QA engineers to narrow specification scope and define user value. Other work includes database optimization to reduce load, speeding up automated tests, improving CI/CD, resolving technical debt, and tuning performance in a large-scale service.

The position is intended for an engineer with backend strengths who can also contribute across web frontend, infrastructure, and product management areas. The role involves leading specifications and architecture rather than only implementing predetermined requirements. The named technology stack includes Open API 3 with Swagger, React, Redux, Rails, Lambda, SNS, SQS, and Firebase.

Required qualifications are at least three years of professional web application development experience; practical experience in both server-side development and web frontend development; experience using AI tools such as GitHub Copilot or Claude Code in development or coding; and experience advancing specifications and team development through flat discussion with other roles, including product managers and designers, in an agile environment such as Scrum.

Preferred experience includes designing and developing a service from the ground up and operating it end to end, including infrastructure such as AWS or Kubernetes; leading other engineers from product-management or technical-management perspectives; performing comprehensive database and CI/CD performance tuning for a large user base; and leading the resolution of technical debt or large-scale refactoring.

The position is full-time with a three-month probationary period. The work location is the Tokyo headquarters in Shinagawa, Tokyo, and the location may change because of business circumstances or office relocation. Working hours follow a discretionary labor system with eight deemed hours per day. Holidays include Saturdays, Sundays, public holidays, and the year-end and New Year holiday period. Paid leave is granted at joining, and six paid sick-leave days are provided annually. Insurance includes employment insurance, workers' compensation insurance, employees' pension insurance, and health insurance. Indoor smoking is prohibited. Online interviews are available.