This position is closed and is no longer accepting applications.

Full-stack Customer Engineer

KOMOJU Musashino-Shi, Tokyo May 27 2025
  • 💴 ¥6M ~ ¥9M annually
  • 🏡
    Fully remote
    From Japan
  • 🌏
    Apply from abroad
    Relocate to Japan
  • 💬
    Business Japanese
    Business English
  • 🧪
    Intermediate level
    Unspecified years of experience

About KOMOJU

KOMOJU Musashino-Shi, Tokyo

The leading cross-border payment gateway for Japan. We power payments for companies like video game distribution platform Steam and the popular mobile app TikTok.

Key benefits

  • Developer-centric, inclusive culture
  • International at our core
  • Generous holiday policy

About the position

The Customer Engineering team at KOMOJU is quite unique - it’s not about promoting our product or managing customer complaints. We do any engineering work that helps us better serve our customers. This involves debugging, contributing to code development, creating an internal knowledge base, writing customer communications, collecting feedback on procedures, and updating internal systems.

The primary responsibility of the Full-stack Customer Engineer is to promptly resolve customer-reported issues in collaboration with the Customer Success team. As part of your regular duties, you will monitor our internal systems and promptly respond to any requests for technical assistance. In response to the request, you will engage in comprehensive engineering activities such as analysing logs, replicating customer-reported issues, debugging, implementing solutions, modifying our codebase, and enhancing our offerings.

The ideal candidates for us are those who excel in a dynamic environment and are consistently seeking ways to enhance the customer experience. We are seeking an individual who is self-motivated and versatile, with a passion for problem-solving and technical research, a willingness to engage in engineering tasks to solve problems directly, and a talent for making quick, well-informed decisions under pressure.

Learn more about the position in this interview with our head of customer engineering.

Responsibilities

  • Respond quickly to technical inquiries from customers received through our customer-facing teams, particularly the Customer Success team.
  • Investigate the mechanism and cause of customer-reported issues.
  • Develop solutions and workarounds for the technical challenges that customers are facing.
  • Collaborate with engineering teams to tackle the most complex issues.
  • Contribute to our codebase to instantly enhance our offerings.
  • Empower our customer-facing teams by providing them with product-related knowledge and insights on commonly reported issues.
  • Represent our customers and partners by advocating the voice of customers and sponsoring feature requests
  • Oversee incident processes and coordinate incident response
  • Be open to communicate with our customers directly

Requirements

  • Strong passion to serve customers
  • Passion for solving real-world problems through technology and creativity.
  • Clear, logical thinking combined with empathetic understanding of customer sentiment, and detailed and unbiased observations.
  • Extensive experience in any programming language and systematic debugging.
  • Concrete understanding of HTTP, WWW, REST, SQL, logging, tracing, and observability.
  • Japanese proficiency at the N2 level

Nice to haves

While not specifically required, tell us if you have any of the following.

  • Professional experience in payment processing systems
  • Professional or hobby experience with applications that accept payments
  • Professional or hobby experience with:
    • Ruby and Ruby on Rails
    • Datadog
    • Shopify
    • PHP
    • TypeScript
    • Amazon Web Services
    • Docker
  • Professional or hobby experience in debugging complex software and proposing code changes
  • Professional, hobby, or academic experience with experimental research.
  • Interest in foreign languages and cultural exchange, with a desire to engage in continuous learning.

Compensation

¥6,000,000 ~ ¥9,000,000 annually.

Hiring Process

  1. 1

    Initial screening call with HR

    To understand candidates’ overall professional background, career aspirations, and to evaluate the fit for the role/ culture.

  2. 2

    Take-home exercise

    It’s opportunity to evaluate candidates’ practical experience and observe that they follow best practices.This includes, but is not limited to, their coding skills, problem-solving abilities, system design capabilities and ability to optimize and maintain code. We normally give the applicant one week to complete it, but we don’t expect it to take more than 2 hours.

  3. 3

    Technical team interview

    This interview serves two purposes: it’s a chance to review the take-home exercise and assess the candidate’s technical abilities, and it also helps evaluate their soft skills, how well they collaborate with stakeholders and team members, manage their work (time management, prioritization, adaptability), and demonstrate a commitment to continuous learning.

  4. 4

    Final interview with leadership

    We’re looking here to assess culture add. We’re not looking for people that just fit the status quo (culture fit), we want candidates who can bring something new and valuable to our culture. While ensuring that they still align with our core values, we want to assess their ability to adapt to recent changes within the organization and to help guide the organization through its next stage of development.

Meet KOMOJU's Developers

Kazunori initially joined KOMOJU as a web application engineer, but by identifying problems he wanted to fix, his role shifted first to VP of Infrastructure, and then VP of Payment Products.

Read their story...

Nicole joined KOMOJU in 2020, and worked her way up to be technical lead of the merchant management team. She shares her journey, how KOMOJU supported her career growth and how the company is adapting to its growing needs.

Read their story...
Photo of Richard Ramsden

Becoming CTO of KOMOJU

with Richard Ramsden

After graduating from university, Richard came to Japan and found a job as a software developer. Eventually he joined KOMOJU, where he rose to the role of CTO.

Read their story...

Nigel was fresh out of college when he joined KOMOJU as a developer. He's now risen to tech lead, where he's helped build out their payment platform while maintaining a healthy work-life balance.

Read their story...

Muhammad Denaw, Senior Site Reliability Engineer at Komoju, talks about his work and shares how Komoju's trust and support propelled him to a promotion.

Read their story...

Head of Customer Engineering Makoto Mizukami describes the unconventional candidates his unique team is looking for.

Read their story...

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