Senior Frontend Engineer

Tokyo, Japan (MJHQ)
1 - Software Development – Frontend System Team /
Full Time, ENG JD /
As a Senior Frontend Engineer at Mujin, you will guide junior team members and enhance the efficiency of our real-time user interface.
The Frontend Team at Mujin is devoted to refining the user experience and interface of our robot controller's web UI. You will collaborate with skilled and committed engineers who possess expertise in this field. Read our team's interview article here:> At the forefront of building ”industrial robots for everyone”


    • Develop and implement high-quality frontend applications using React and TypeScript, adhering to best practices and coding standards.
    • Create and maintain reusable components and libraries to promote consistency and efficiency across projects.
    • Optimize application performance by analyzing code, profiling, reducing bundle size, and leveraging browser APIs where possible.
    • Ensure the application is responsive and works seamlessly across different browsers and devices.
    • Review code and mentor junior developers to ensure quality and adherence to coding standards.

Minimum Requirements

    • Extensive knowledge of JavaScript, TypeScript, React, and CSS.
    • Experience creating visual effects and animations using CSS and SVG.
    • Familiarity with Webpack, Rollup, esbuild, or other bundling tools. Comfortable creating and maintaining bundler configurations.
    • Extensive knowledge of web application optimization.
    • Proven track record of maintaining JavaScript libraries.
    • Experience with Jest, Mocha, Testing Library, or other testing frameworks, and deep understanding of CI/CD pipelines.

Preferable Requirements

    • Experience with Figma plugin development.
    • Familiarity with GraphQL.
    • Experience with PixiJS for building rich and interactive web applications.
    • Ability to automate code quality checks with Eslint and SonarQube to ensure the highest code quality.
    • Knowledge of Rust and Web Assembly for building performant and efficient web applications.
    • Familiarity with i18n to develop applications that can be easily localized.


    • We work in a fast-paced, agile environment where we constantly collaborate, review ideas amongst peers, and test proposed solutions. We encourage continuous learning and brainstorming within our teams. We are focused on solving real-world problems and your contributions are deployed at an amazingly fast pace to empower industrial robots to perform tasks that were previously impossible.
    • Japan is known for its robotics technology. If you are coming to Japan why not work with products you can only build in this country?

3-8-5 Tatsumi, Koto-ku, Tokyo 135-0053, Japan
Nearest Station: Tatsumi Station, Shinonome Station

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

・Flexible, depending on experience and skills
・Salary revision twice a year
・Additional bonuses or incentives may be available based on performance

・Two days off per week (Every Saturday and Sunday)
・Annual paid leave
・Year-end vacations
・Celebration or condolence leave
・Family caregiver leave
・Maternity leave
・Childcare leave
・Other holidays as defined by the company

Company Benefits
・Flexible dress code policy
・Commuting allowance
・Social insurance (including Employment, Industrial Accident Compensation, Health Insurance, and Pension)
Free buffet lunch every workday
Free vending machines (offering drinks and snacks)
High-end coffee machine
Exclusive Employee Gym Access
・Monthly team dinner support

Relocation Support
If you relocate from outside of Japan, we will provide the following support.
・Visa sponsorship
・One-way flight to Japan
・Shipping expenses covered up to a specified limit
・Temporary housing assist
・Permanent housing assist