Frontend Engineer（Android-heavy, React secondary）

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 that support long-running workflows and mission-critical operations at scale.

Responsibilities

Android

- Design, develop, and maintain Android applications for industry devices used in warehouse environments.

- Implement features that interface directly with device hardware layers, including barcode scanners, cameras, physical buttons, NFC/RFID, printers, Bluetooth, and other peripherals.

- Work with vendor-specific SDKs.

- Debug and resolve issues across application, OS, and device layers.

- Build applications optimized for offline usage, long-running sessions, and high reliability.

Web Frontend

- Develop web frontend applications using React and TypeScript.

- Ensure applications are responsive, accessible, and work across browsers and devices.

- Optimize frontend performance through profiling, bundle size reduction, and effective use of browser APIs.

Collaboration & Quality

- Collaborate with Product Managers, Designers, backend engineers, and operations teams.

- Participate in code reviews, knowledge sharing, and mentoring.

- Triage, debug, and resolve production issues across Android and web systems.

- Contribute to CI/CD pipelines, testing, and code quality improvements.

Tech Stack

Android

- Kotlin, React Native

- Android SDK, Android Jetpack

- AOSP-based devices, OEM SDKs

Web Frontend

- TypeScript, React

Tooling & Build

- Rsbuild

- Vitest

- ESLint

Backend & Infrastructure

- Python

- RESTful APIs

- GraphQL

- Docker

Collaboration

- Figma

- Confluence

- GitLab

• 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.
• Solid understanding of software engineering fundamentals and performance optimization.

• Experience developing applications for industrial devices.
• Proven experience maintaining shared frontend libraries or component systems.
• Experience with frontend performance monitoring and optimization.
• Familiarity with PixiJS, rich animations, or interactive UIs.
• Experience with offline-first design and data synchronization.
• Experience with Figma plugin development.
• Experience with i18n and localization workflows.

• We are looking for those who are prepared to dedicate themselves to facing big challenges, work proactively and independently, and take ownership when working with members across the teams!
• You will get your “hands dirty” working on all aspects of the industrial robot controller, not being confined to a specific component in the system. The work is challenging, mostly like something that you have never done before, requiring extensive research.
• Balanced, Modern Client-Side Tech Stack

• Coding Assessment: Initial technical evaluation.
• HR Interview: Discussion with Human Resources.
• Hiring Manager Interview: One or two rounds with the hiring manager.
• Take-Home Assignment & Feedback Interview (If Applicable): A task to complete on your own, followed by a feedback session.

Location

3-8-5 Tatsumi, Koto-Ku, Tokyo 135-0053, Japan

Work Hours

8:45 - 17:45 (with a 60-minute break)

Salary

・Based on experience and skills

・Salary revision twice a year

・Additional bonuses available based on performance

Holidays

・Every Saturday and Sunday

・Annual paid leaves

・Maternity leave and Childcare leave

・Other holidays as defined by the company

Company Benefits

・Flexible dress code policy

・Commuting allowance

・Japanese Social Security (Health Insurance, Pension, Labor Insurance)

・Monthly team dinner support

・Free buffet lunch every workday

・Free vending machines (offering drinks and snacks)

・High-end coffee machine

・Exclusive Employee Gym Access

Japan Relocation Support

・Visa sponsorship

・Flight ticket support

・Shipping expenses coverage up to a specified limit

・Assistance for housing