Frontend Engineer

Builder Work is a construction-industry job and career-change service initially focused on recruitment and placement. The role builds its frontend as the service develops a proprietary matching engine and future services such as direct sourcing and qualification support.

Working under the engineering lead, the engineer designs and develops the user-facing experience for jobseekers, hiring companies, and internal operations. Responsibilities include screen design, development, testing, operation, refactoring, UI/UX improvements based on KPIs and user behavior, collaboration with UI/UX designers, code reviews, and resolving specifications with the planning team while deciding implementation approaches.

The work covers jobseeker registration and job-search flows, internal operation screens, frontend implementations for AI functions such as automatic résumé generation using LLMs, and screens for web and application-based qualification support and reskilling services. The team also uses AI coding agents such as Claude Code in implementation, code review, investigation, and testing, including PR reviews, dependency updates, security checks, and end-to-end testing.

Required qualifications are at least three years of web-service development experience as a frontend engineer, development and operational experience with TypeScript, frontend development using React or Next.js, foundational HTML, CSS, and JavaScript knowledge, responsive web design experience, and team development with Git. The posting also seeks people who can work proactively and independently and support the missions of Builder Work and ANDPAD.

Preferred experience includes UI/UX knowledge, collaboration with designers, design-system development, frontend test automation, performance improvement, UI improvement using KPIs and behavioral logs, specification work with planning or business teams, cross-browser and mobile development, generative AI or LLM feature implementation, and knowledge of HR or the construction industry.

The position is based at the dedicated Builder Work project office in Suidobashi, Tokyo. Work is primarily office-based, with remote work available for consultation. Working hours are 10:00–19:00 under a flextime system with core hours from 11:00–15:00. Employment is permanent with a three-month probation period during which conditions do not change. The listing states that annual compensation is individually determined according to experience and ability; the structured listing gives annual values of 6,000,000–10,000,000 JPY. Salary revisions and bonuses are provided twice a year. Benefits include social insurance, book-purchase assistance, an employee stock ownership plan, commuting and remote-work allowances, and other listed benefits. Holidays include weekends and public holidays, paid leave, seasonal and year-end holidays, childcare and nursing-care leave, and condolence leave. Interviews are currently conducted online, with two or three interviews and a possible personnel meeting; reference letters from two former colleagues are requested.