Job title: Senior Product Engineer, Partner Product Development Department, Tokyo
Job type: Permanent
Emp type: Full-time
Industry: IT & Telecommunications / IT・通信
Functional Expertise: Technical (IT) / 技術職(IT)
Skills: Technology Stack • Backend: Kotlin GraphQL Ruby on Rails • Frontend: React.js Next.js TypeScript • Middleware: MySQL Kafka Debezium • Infrastructure: AWS Docker Kubernetes Terraform • CI/CD: CircleCI GitHub Actions Argo CD • Monitoring: Datadog Rollbar • Task Management: JIRA Tools Used • Communication: Slack Zoom
Salary: Negotiable
Location: Minato City, Tokyo
Job published: 2026-07-13
Job ID: 73791

Job Description

Overview

You will join the Partner Product Development Department within the SMB Business Domain, responsible for developing products for professional partners such as accounting firms and labor & social security attorney offices.

The department focuses on solving challenges faced by accounting firms in Japan by improving productivity, increasing the value they deliver to clients, and supporting mutual business growth.

Responsibilities

The team is committed to improving the advisory experience for professional partners who support the growth of small and medium-sized businesses (SMEs).

Many accounting firms still spend significant time on manual administrative tasks such as receipt management and document preparation, limiting the time available for higher-value advisory services.

The organization develops cloud-based back-office SaaS solutions that accelerate the digital transformation of SMEs. The cloud accounting platform is widely adopted by accounting firms across Japan.

The engineering team follows Scrum development and does not separate Frontend and Backend responsibilities. Engineers are encouraged to contribute across the full stack while maintaining a strong product mindset.

English is becoming the primary language for software development, although some communication may still be conducted in Japanese during the transition period. Conversational Japanese is considered a plus.

Required Skills & Experience

Product & Communication

  • Strong product mindset with experience in product discovery, user workflow design, and feature validation
  • Ability to understand user workflows and evaluate product specifications
  • Ability to identify design risks and technical constraints
  • Strong communication skills with both technical and non-technical stakeholders
  • Ability to organize objectives, constraints, and risks while driving technical decisions

Technical Skills

  • Bachelor's degree in Computer Science, Engineering, or equivalent experience
  • 5+ years of web application development experience with a full-stack mindset
  • Experience with:

Frontend

  • React
  • Next.js
  • GraphQL
  • REST APIs

Backend

  • Java
  • Kotlin (Spring Boot)
  • Ruby on Rails
  • Experience designing, deploying, and operating cloud infrastructure
  • Experience using AI-assisted development tools while maintaining code quality
  • Willingness to relocate to Japan and commute to the Tokyo office at least twice per week

Preferred Qualifications

  • Conversational Japanese skills
  • Experience with Ruby on Rails and RDBMS
  • System architecture design experience
  • Microservices experience
  • Scrum development experience
  • DevOps practices
  • Container technologies
  • Test-driven development (TDD)
  • Experience developing AI solutions or leveraging AI tools to improve software development

Language Requirements

Japanese

  • No Japanese language requirement, but willingness to learn is expected

English

  • English proficiency equivalent to TOEIC 700+ or the ability to participate in meetings and written communication in English shortly after joining

Equivalent qualifications such as TOEFL, IELTS, EIKEN, or Cambridge English are also accepted.

Candidates without an equivalent qualification may be asked to complete an English assessment during the interview process.

Technology Stack

Backend

  • Kotlin
  • GraphQL
  • Ruby on Rails

Frontend

  • React.js
  • Next.js
  • TypeScript

Infrastructure & DevOps

  • AWS
  • Docker
  • Kubernetes
  • Terraform
  • MySQL
  • Kafka
  • Debezium
  • CircleCI
  • GitHub Actions
  • Argo CD

Monitoring

  • Datadog
  • Rollbar

Project Management

  • Jira

Communication Tools

  • Slack
  • Zoom

Work Environment

The company provides a modern engineering environment designed to support world-class software development.

Benefits include:

  • Latest Mac or Windows laptops
  • Budget for monitors, keyboards, mice, and other peripherals
  • Company-sponsored technical library
  • Employee referral program
  • Support for attending domestic and international technology conferences