Senior Frontend Engineer (SR)

Job Description Career Opportunity for a Senior Frontend Engineer in Japan! ■ Senior Frontend Engineer ■ Company Overview A Japan-originated global Web3 technology company building next-generation blockchain infrastructure, decentralized applications, and on-chain products. With strong partnerships across major global enterprises and financial institutions, it is focused on bringing blockchain technology into mainstream use and building the infrastructure for the next generation of the internet. ■ Your Role And Responsibilities Frontend architecture & technical contributions: Contribute to the evolution of frontend system design, patterns, and best practices.Application development: Design, build, and maintain complex, production-grade frontend applications using TypeScript and TanStack Start.State management & data orchestration: Implement and maintain scalable client-side state using Zustand and TanStack Query to ensure predictable and performant data flows.Project ownership: Own and deliver end-to-end frontend workstreams, Including Core wallet and account abstraction UX flowsHigh-throughput, data-rich product interfacesNew web and mobile dApp surfacesTesting & reliability: Contribute to and maintain Playwright-based end-to-end test suites to improve coverage and release confidence.Cross-functional collaboration: Partner with Product, Design, and Backend teams to refine requirements and deliver high-quality outcomes. ■ Experience And Qualifications 2 ~ 4 years of experience as a frontend engineerStrong proficiency in TypeScript and modern JavaScript.Experience with TanStack Start or comparable meta-frameworks (e.g. Next.js, Remix).Solid expertise in modern React patterns, performance optimization, and frontend application design.Ability to operate independently in ambiguous, fast-paced environments.Excellent written and verbal communication skills. ■ Additional Preferred Qualifications Experience leveraging AI-assisted coding tools (Cursor, Copilot, Claude, or similar) to accelerate development.Background in web3, blockchain, or decentralized application development.Experience in startup or scale-up environments. ■ Good Reasons to Join Gain exposure to collaborations with leading technology, financial, and enterprise organizations. ■ Work Location Tokyo, Japan Details will be provided during the meeting.