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Senior / Full-Stack Engineer (JavaScript · Python · SQL) — Contract Management System Development Group — Tokyo

Role Overview

We are building and evolving the core contract management systems that power KINTO's subscription and fleet services. As a Senior Full-Stack Engineer, you will lead feature development across both frontend and backend, working with a modern stack in a product-driven team.


Responsibilities

  • Design and implement features across frontend (JavaScript/TypeScript) and backend (Python)
  • Write and optimise complex SQL queries for contract data management
  • Participate in architecture decisions and technical design reviews
  • Collaborate with product managers and stakeholders to refine requirements
  • Review code and mentor other engineers
  • Improve system performance, maintainability, and test coverage

Requirements

  • 5+ years of full-stack or combined frontend/backend experience
  • Strong JavaScript / TypeScript skills (React, Vue, or similar)
  • Proficiency in Python for backend development
  • Strong SQL skills (query optimisation, schema design)
  • Experience with AWS or comparable cloud infrastructure
  • Business-level Japanese

Nice to Have

  • Experience with contract, billing, or subscription management systems
  • Familiarity with Domain-Driven Design or Clean Architecture
  • GraphQL experience
  • English communication skills

What We Offer

  • Competitive senior-level salary
  • Hybrid work arrangements, Tokyo office
  • Direct ownership over a business-critical internal platform
Apply Now

This is the English version of the original Japanese job listing. For the Japanese version, please visit the official KINTO Technologies recruitment page.