Backend API Engineer

Location: Tokyo, on-site Language: English required, Japanese a plus Experience: 3+ years designing and building REST APIs in Python (FastAPI or Django REST Framework). Comfortable defining endpoints, request and response schemas, status codes, validation, and error handling. We're building a product-first company transforming how people file taxes: automating what others still do manually. Our app helps turn tax filing from slow and messy into something clear, fast, and (yes) enjoyable. We're now hiring a Backend Engineer to join our high-ownership engineering team. The Backend API Engineer (Python/REST APIs) will be responsible for designing, implementing, and maintaining server-side features that power FreedomTax Japan’s tax platform. Day-to-day tasks include building and optimizing APIs, integrating with databases and third-party services, and ensuring secure, reliable data processing for Japanese and U.S. tax workflows. The role also involves collaborating with front-end engineers, product managers, and accountants to translate business requirements into scalable technical solutions, as well as troubleshooting and improving existing code. This is a full-time, on-site role based in Tokyo, Japan. Qualifications Strong skills in Back-End Web Development and Programming, with professional experience building and maintaining production web services.Proficiency in Software Development and Object-Oriented Programming (OOP), including writing clean, testable, and maintainable Python code.Basic familiarity with Front-End Development concepts to collaborate effectively with front-end engineers on API design and data structures.Experience with RESTful APIs, relational databases (e.g., PostgreSQL, MySQL), and version control systems such as Git.Knowledge of security best practices, performance optimization, and error handling in backend systems.Bachelor’s degree in Computer Science, Software Engineering, or a related field, or equivalent practical experience.Ability to work collaboratively in a cross-functional team, communicate clearly, and document technical decisions.Comfort working in an international environment; business-level English required, Japanese language skills are an asset. Why Join Us Meaningful problems: Document processing, data pipelines, and workflows that directly impact how people file their taxes.Great team: Work directly with the founder and a senior backend engineer in a low-bureaucracy environmentWork that matters: Build something people genuinely need—not just another CRUD app or internal toolFast-moving environment: High iteration speed, direct feedback, real product impactReal ownership: You'll own projects end-to-end with clear success metrics—not just tickets in a queue ✏️ How to Apply Apply via LinkedIn. Include a short note (3–5 sentences) describing one API endpoint you built: the HTTP method, the route, what it returns on success, and what it returns when the request is invalid.