Lead Frontend Product Engineer

Role OverviewAs a Lead Frontend Engineer, you will own the end-to-end direction of our frontend applications used across convenience-store robotics operations. You will collaborate closely with business teams to clarify requirements, work with designers on implementation-ready specifications, and lead the prototyping → implementation → release workflow. You will guide two existing frontend engineers as a player-coach while continuing to contribute hands-on.You will work in an English-speaking engineering team while delivering a product primarily for Japanese end users. While Japanese managers and business stakeholders can communicate in English, a significant portion of the input information and business context is in Japanese.Team & Platform ContextWe are planning to migrate our legacy Unity-based 2D application to a modern WebView-based architecture in the future. Currently, we are in the initial phase of building a simple web application using TypeScript and React, which integrates with a newly developed .NET REST API backend. While our broader ecosystem relies on C#, gRPC, and Azure, this role focuses on establishing this new web-standard client layer from the ground up. Historically, engineers touched all components; as we scale, we are specializing roles. You will lead the frontend domain, bridging the gap between complex robotics data and intuitive user experiences, while laying the groundwork for a unified multi-platform client application.The Challenge: Software Meets HardwareBecause our software applications (spanning both frontend and backend) serve as the direct interface for end-users, we face a constant stream of diverse and evolving requirements. You will work in a unique environment where software speed meets hardware reality: Bridging the Cycle Gap: Hardware and Automation development cycles are inherently longer than pure software. You will often need to devise creative software workarounds to mitigate hardware issues or implement "virtual" features to validate business value before hardware is ready Elevating Engineering Standards: While our hardware and automation teams are experts in their fields, they may be less familiar with modern SaaS practices or non-functional requirements (NFRs). You will act as a bridge, supporting other teams with general software development know-how and ensuring the overall system is robust and scalableThis role requires more than just coding; it demands the flexibility to navigate constraints and the leadership to raise the bar for software engineering across the organization.Key ResponsibilitiesLeadership & OwnershipTechnical Strategy: Establish the architectural foundation for the new frontend application, making pragmatic choices that ensure maintainability and future scalabilityTeam Mentorship: Act as a player-coach, actively writing code while mentoring engineers through code reviews, pair programming, and technical guidanceProduct Delivery: Lead the end-to-end delivery lifecycle—from requirement definition and design review to implementation, release, and post-deployment monitoringCross-Functional Collaboration: Partner with backend (.NET), design, robotics, and operations teams to ensure high-quality, integrated user experiencesTechnical Execution & ArchitectureCore Development: Design and implement complex frontend features using TypeScript and modern React, setting the standard for code qualityArchitecture Evolution: Evolve application architecture, focusing on state management, routing, performance tuning, and error handlingAPI Integration: Architect robust integration patterns with backend services via REST and gRPCMulti-Platform Strategy: Support delivery across multiple targets (Web, WebView-based mobile apps)Reliability & Ops: Ensure system reliability through comprehensive instrumentation (logging, metrics, error tracking) and lead incident resolutionContinuous ImprovementTech Radar: Stay current with emerging frontend technologies and propose platform improvementsProcess Optimization: Contribute to a culture of continuous learning, refining agile workflows and CI/CD processesTech StackFrontend: TypeScript, React, Next.js, React Router, Blazor, HTML5, CSS3 (Tailwind CSS, shadcn/ui)Backend: gRPC, REST API, C#/.NETCloud & Infrastructure: Microsoft Azure, Docker, KubernetesDevelopment Tools: Git/GitHub, CI/CD (GitHub Actions, Azure DevOps)Design Tools: FigmaProject Management: Agile methodologies, Jira, ConfluenceRequirements - Must-Have6+ years of professional experience as a software engineer3+ years of hands-on experience with TypeScript and React3+ years of experience developing applications for real users, including release and operation phasesExperience in team development using Git with 5 or more engineersExperience mentoring engineering team membersExperience participating in technical decision-makingExperience collaborating closely with business and design teamsExperience developing WebView-based mobile applicationsAbility to communicate effectively in EnglishWillingness or ability to understand Japanese documentation and context (input is often in Japanese)Requirements - Nice-to-HaveExperience working in both early-stage startups and established large-scale organizationsAbility to communicate in JapaneseExperience collaborating with .NET/C# backend teamsExperience with .NET/C# backend developmentExperience with BlazorExperience with frontend observability (error logs, performance metrics, user flow instrumentation)Experience with automated testing tools (Jest, Testing Library, Cypress, Playwright)Experience in robotics, IoT, or dashboards requiring real-time telemetrySoft Skills & BehaviorsBalanced Mindset: You understand the trade-off between startup agility and the reliability required for enterprise systems. You can drive uncertain products to launch while ensuring stability through pragmatic quality practicesSelf-Managed & Resilient: You excel in unstructured environments with shifting business requirements, managing your own tasks and stress levels effectivelyCommunication Bridge: You can explain technical trade-offs to non-engineering members and propose alternatives in plain languageClarifier: Comfortable leading ambiguous discussions and forming clarity from rough requirementsTeam Builder: Invested in developing the skills and productivity of the frontend team through mentoring and process improvementsCollaborative Owner: Low-ego, proactive, and solution-oriented; you take initiative to identify problems and drive them to completionWe may use artificial intelligence (AI) tools to support parts of the hiring process, such as reviewing applications, analyzing resumes, or assessing responses. These tools assist our recruitment team but do not replace human judgment. Final hiring decisions are ultimately made by humans. If you would like more information about how your data is processed, please contact us.The annual salary range for this position is depending on experience and skills. Additional performance-based bonuses and benefits may be available. We value transparency regarding compensation—final offers are determined by your qualifications and role responsibilities in line with our compensation guidelines. All employees receive social insurance, paid leave, and opportunities for professional development.