Software Engineer (Go / TypeScript / AI-Driven Development)

About the Role

We are looking for a versatile Software Engineer who prioritizes foundational engineering principles over ephemeral frameworks. In this role, you will leverage Go and TypeScript to build resilient systems while actively adopting cutting-edge, AI-driven development methodologies.

You thrive in an autonomous, high-ownership startup environment, balancing independent execution with clear, proactive communication across a diverse team.

Responsibilities

• Design, build, and maintain high-performance, reliable systems primarily using Go and TypeScript.
• Explore and integrate AI-assisted development tools and workflows to enhance team productivity and system capabilities.
• Collaborate on cloud and infrastructure architecture to ensure scalability and resilience.
• Take full ownership of features from technical conception to production deployment.
• Communicate transparently with cross-functional teammates, proactively identifying and removing blockers.

Requirements

• Strong grasp of core programming concepts, design patterns, clean architecture, and computer science fundamentals.
• Hands-on development experience with Go and/or TypeScript.
• Self-directed and self-managing, with excellent collaborative and interpersonal communication skills (no siloed working).
• Strong passion for and curiosity about AI-driven software development.
• Passion for working in a fast-paced, iterative startup environment.
• Business-level Japanese proficiency (capable of handling technical alignment and cross-team communication in Japanese).

Nice-to-Haves

• Experience designing, maintaining, or operating cloud infrastructure (AWS/GCP), containers, and CI/CD pipelines.
• Practical track record of using AI tools (e.g., LLM APIs, Copilot, Cursor) within daily development workflows.
• Professional English proficiency or experience working in multicultural/multilingual environments (a strong willingness to learn and use English is also welcome).
• Experience architecting systems from scratch or scaling products through rapid growth phases.

Remote Policy

• In-Office Policy: Optional weekly office days on Thursdays at our Shinagawa Station office (encouraged if you live within commuting distance).
• Retreats: Mandatory in-office attendance for company retreats a few times per year