Frontend Engineer（Android-heavy, React secondary）

About Mujin

Mujin creates MujinOS, the intelligent operating system for industrial robotics. By leveraging real-time digital twins, MujinOS seamlessly connects and orchestrates equipment to achieve fully autonomous operations.

At our core is Machine Intelligence (MujinMI), a unique approach offering advanced perception, planning, and control algorithms that solve the most challenging automation problems. Trusted by globally recognized companies, we are redefining supply chain efficiency. Headquartered in Japan with growing teams in China, the US, and Europe, we invite you to join a dynamic environment where you can shape the future of automation.

Team Introduction

As a Software Engineer on Mujin’s Warehouse Execution System (WES) & Fleet Management (FM) team, you will focus on developing user-facing Android and web frontend applications used daily in warehouse operations. Your work directly shapes how operators interact with warehouse systems through industrial Android devices and browser-based interfaces.

The team specializes in building reliable, high-quality frontends that run in demanding production environments, where stability, performance, and usability are critical. You will work closely with backend engineers, product managers, designers, and operations teams to deliver intuitive, responsive, and maintainable interfaces.

Responsibilities

Android

• Design, develop, and maintain Android applications for industry devices used in warehouse environments.
• Implement features that interface directly with device hardware layers (barcode scanners, cameras, physical buttons, NFC/RFID, Bluetooth, etc.).
• Work with vendor-specific SDKs and build applications optimized for offline usage and long-running sessions.

Web Frontend

• Develop web frontend applications using React and TypeScript.
• Ensure applications are responsive, accessible, and optimized for performance across browsers and devices.

Collaboration & Quality

• Collaborate with cross-functional teams (PMs, Designers, Backend, Ops).
• Participate in code reviews, knowledge sharing, and mentoring.
• Triage, debug, and resolve mission-critical production issues across Android and web systems.

Tech Stack

• Android: Kotlin, React Native, Android SDK, Android Jetpack, AOSP-based devices.
• Web Frontend: TypeScript, React, Rsbuild, Vitest, ESLint.
• Backend & Infrastructure: Python, RESTful APIs, GraphQL, Docker.
• Collaboration: Figma, Confluence, GitLab.

Requirements

Minimum Qualifications

• 3+ years of professional software development experience.
• Professional experience developing Android applications using Kotlin and/or Java.
• Strong knowledge of JavaScript, TypeScript, React, and CSS.
• Experience integrating applications with device hardware features or SDKs.
• Experience with testing frameworks and CI/CD pipelines.

Preferable Qualifications

• Experience developing applications for industrial devices.
• Proven experience maintaining shared frontend libraries or component systems.
• Familiarity with PixiJS, rich animations, or interactive UIs.
• Experience with offline-first design and data synchronization.

Work Environment & Benefits

• Location: Tatsumi, Koto-Ku, Tokyo.
• Work Hours: 8:45 - 17:45 (includes 60-minute break).
• Salary: Based on experience; revision twice a year; performance bonuses available.
• Food & Health: Free buffet lunch every workday, free snacks/drinks, and access to an exclusive employee gym.
• Relocation Support: Visa sponsorship, flight ticket support, shipping expense coverage, and housing assistance.

Interview Process

1. Coding Assessment
2. HR Interview
3. Hiring Manager Interview (1-2 rounds)
4. Take-Home Assignment & Feedback (If applicable)