Full Stack Developer
Applications: candidates may apply from outside Japan. Visa sponsorship: available. Japanese: Not required. English: Business level. Japan Dev tags: Engineering, Web / Full-stack, Go, React, PostgreSQL.
Full-Stack Developer
About the Role
We’re looking for a Full-Stack Developer who is excited to build scalable, resilient systems and elegant user experiences at an early-stage startup. You’ll own features end-to-end — from design and architecture to implementation and refactoring — while balancing immediate delivery with long-term technical health.
This role is ideal for someone who thrives in a fast-paced environment, has a proactive mindset, and wants to shape both product and engineering foundations.
Responsibilities
- Design and implement new features across frontend and backend.
- Architect systems thoughtfully (DB schema, internal communication, data flows) to enable feature scalability and robustness.
- Take ownership of delivering individual features end-to-end.
- Monitor tech debt and drive proactive refactoring.
- Make smart trade-offs between speed and scalability when implementing features.
- Continuously refine systems to support future growth.
Requirements
Must-Haves
- Full-stack development capability (even if frontend-leaning).
- If experienced, at least 2 years tenure at a single organization is preferred.
- History of internal promotion is strongly preferred.
- Proactive in identifying problems before they occur and taking action.
- High intrinsic intelligence with the ability to make sound short-term and long-term technical decisions.
Preferred Qualifications
- Excitement about working in an early-stage startup.
- Curiosity and enthusiasm for new technologies.
- Experience in the fintech/payments space is a plus.
- Hands-on experience with some of the following:
Frontend Stack
- HTML/CSS
- Tailwind
- Svelte / SvelteKit
- React
- TypeScript
Backend & Infrastructure Stack
- Go (Chi)
- ConnectRPC/gRRC
- Protobuf / Bufbuild
- Temporal
- AWS
- Terraform
- Git / GitHub
- PostgreSQL
Why Join Us?
- Impact from day one: Shape the foundations of both product and engineering.
- Growth opportunities: Be part of a small, ambitious team where your contributions are recognized.
- Challenging problems: Work on complex systems that require thoughtful design and proactive innovation.
- Culture of ownership: We value people who take initiative and push boundaries.