We’re looking for a Senior Software Engineer who is passionate about building reliable, scalable, and maintainable systems—from backend business logic to frontend user experiences.
You’ll work primarily with TypeScript, with React on the frontend and Nest.js/Prisma on the backend. You’ll collaborate closely with both engineers and non-engineers (product, design, biz/ops) to ship features that power the core of our product for some of Japan’s largest enterprise customers.
You’ll have the opportunity to:
- Design and deliver features end-to-end across the stack (frontend, backend, architecture)
- Take ownership of technically challenging projects, such as algorithm optimization, complex data modeling, or new platform integrations
- Shape and evolve our core backend and data persistence layers
- Drive improvements in system reliability, performance, and maintainability
- Mentor other engineers and champion high standards in code quality and architecture
- Contribute to key open source projects and upstream dependencies as part of your normal workflow
We value engineers who care deeply about technical quality, end-user experience, and long-term stability—not just shipping tickets fast.
Requirements
- 5+ years of professional software engineering experience
- Significant experience with TypeScript
- 2+ years of hands-on work with React (or a similar modern frontend framework)
- Strong understanding of backend frameworks, database modeling (SQL/Prisma), and asynchronous app architecture
- Proficiency collaborating across functions (product, design, operations, and stakeholders)
- Track record of delivering production systems with an emphasis on reliability, testability, and maintainability
- Familiarity with modern development workflows: Git, PR reviews, CI/CD, and automated testing
Nice to haves
While not specifically required, tell us if you have any of the following.
- Development and operation using containers (e.g. Docker)
- Cloud infrastructure experience (e.g. AWS or GCP)
- Machine learning or recommendation engines
- Performance measurement and bottleneck investigation
- Conversational-level Japanese (equivalent to JLPT N3 or greater).
Compensation
¥7,500,000 ~ ¥10,000,000 annually.