Job Description

Join a leading payment solutions provider and help ensure the quality and reliability of our global payment systems.

N3 Japanese needed.

 

■ Job Title

Senior Backend Engineer

 

■ Company Overview

We are a premier provider of cross-border payment solutions in Japan.
Our platform supports thousands of global merchants through developer-centric APIs and seamless integration with major e-commerce platforms.

 

■ Your Role and Responsibilities 

As a backend engineer, you’ll work on core systems that handle global payments. You’ll be responsible for building and maintaining robust, high-performance APIs and services, primarily using Ruby and Ruby on Rails.

This is a product-focused engineering role in a collaborative and inclusive environment where engineers influence both product and technical decisions. You’ll be expected to lead technical projects, mentor team members, and improve the reliability and maintainability of the platform.

While the role is backend-centric, occasional frontend tasks may be required as the team continues to grow.

Key Responsibilities:

Develop and maintain backend systems using Ruby on Rails

Collaborate with product managers to translate requirements into working features

Lead large technical initiatives, from planning and architecture to implementation

Conduct code reviews and participate in architectural discussions

Ensure software quality through testing, monitoring, and continuous improvement

Identify and execute meaningful refactoring and system improvement efforts

 

■ Experience and Qualifications

Proven experience building scalable and high-performance web APIs

Deep understanding of database design, optimization, and access patterns

Ability to architect systems across multiple data sources (including OLAP/OLTP)

Familiarity with observability practices such as monitoring, logging, and tracing

Strong communication skills with an ability to clearly document designs and decisions

Experience integrating with third-party APIs securely and reliably

Knowledge of common web vulnerabilities and secure coding practices

Strong foundation in software architecture, design patterns, and engineering best practices

 

■ Additional Preferred Qualifications

Experience with modern frontend frameworks (TypeScript, Vue.js, or React)

Background in payment systems or fintech

Business-level spoken Japanese

Contributions to open-source projects or tech communities

 

■ Good Reasons to Join

Flexible work arrangements, including remote and in-office options.

Attractive paid leave policies, including summer, winter, and birthday holidays.

Dedicated budget for self-learning and professional development.

Support for Japanese language learning.

 

■ Work Location

(Upon Employment) Tokyo
(Scope of change) Location as specified by the company
Both remote work and office work are possible.

 

■ Salary 

To be decided based on your experience, skill set, and company policies.
Details will be shared during the interview process.

 

Details will be provided during the meeting.