KOMOJU

KOMOJU is a global payment gateway that enables merchants worldwide to accept payments on their websites with ease. With a focus on providing a wide range of payment methods in Japan, South Korea, China, and Europe, KOMOJU is the preferred choice for b...

Internet Software & Services

Information Technology

3 open positions

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Backend Engineer, Ruby

1 month, 3 weeks ago

Japan

Full-time

Mid Level

Backend Engineer

Software Development

Datadog React Ruby Ruby on Rails Shopify Terraform TypeScript Vue.js

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KOMOJU

Internet Software & Services

View All Jobs 3

Description

Build backend systems and APIs for KOMOJU’s payment platform using the Ruby on Rails stack.
Translate product goals and feature requests into working software and clear technical specifications.
Design and execute large technical projects from design through implementation and delivery as part of a team.
Add new APIs for front-end interfaces and collaborate with product and front-end teams on requirements.
Investigate and resolve production bugs and partner integration issues to ensure customer payments process correctly.
Ensure high-quality, reliable software through thorough testing, code reviews, refactoring, and documentation.
Improve system reliability and observability, including work with Terraform and DataDog.
Provide and receive constructive feedback and mentoring within the engineering team to help develop skills and improve the codebase.
Occasionally contribute to front-end tasks (<5%) as needed.

Requirements

Familiarity with Ruby core concepts such as the object hierarchy and metaprogramming features (e.g., method_missing).
Experience building performant, scalable Ruby web applications.
Ability to design data models and overall system architectures.
Strong technical communication skills, including the ability to document decisions clearly and concisely.
Solid knowledge of testing practices and different testing types.
Understanding of common web vulnerabilities and how to mitigate them.
Knowledge of software architecture, design patterns, and engineering best practices.
Nice-to-have: Experience with TypeScript, Vue.js, or React.
Nice-to-have: Experience with payments/payment systems, secure and fault-tolerant integration with third-party APIs, understanding of database performance/data access patterns, and familiarity with monitoring/observability tools such as DataDog.

Benefits

Remote-first work with optional office space for in-person collaboration.
10 days regular vacation plus 5 days summer and 5 days winter vacation.
Paid birthday holiday.
Budget for self-learning allowance and access to the O'Reilly Learning Platform.
Language training for Japanese and English (optional).
Twice-weekly office lunch.

Interested in this position?

Apply directly on the company website

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