Backend Engineer, Ruby

KOMOJU (by Degica) is 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. Today we help thousands of merchants by providing them with the payment infrastructure they need through developer-friendly API’s to integrations on popular platforms like Shopify and Wix; we help our merchants grow in all markets they are expanding.

We are product focused, meaning you will work on our payment gateway and any other projects towards building the future of KOMOJU. You will work with other engineers in a flat and inclusive culture where engineers have a say in both key product and technology decisions. The culture is largely self-organizing, which means engineers have both a stake and ownership in what they work on. Engineers play to their strengths, but are also able to invest in areas where they want to grow within the team. At KOMOJU, you are the main driver behind your growth and position in the company.

Most of our engineering team members come from outside Japan. English is the primary language used, and throughout the company, many people are at least bilingual. Being an international company we know the importance of bilingualism. We offer all employees a choice between optional English and Japanese lessons to help create a culture of diversity and ensure smooth collaboration across teams.

We are looking for a backend engineer to help us build our platform to handle payments on a global scale. You will primarily work with Ruby, building out features using Ruby on Rails (90% of tasks). As we’re still scaling our front-end team, you may be asked occasionally to work on front-end tasks as well (Less than 5% of tasks). As well as this there will be tasks related to Monitoring, Observability etc. which uses Terraform and DataDog (< 5%).

Typical tasks include adding new APIs for Front-end Interfaces in our Ruby on Rails application for customers to use, investigating bugs with our partners to ensure customer payments go through smoothly, and improving our systems’ reliability and observability to ensure better better health using Terraform.

You will work with our product managers and critically evaluate requirements then implement those requirements in code. You will also work with your fellow developers and provide constructive feedback through code reviews, look at refactoring opportunities, and helping improve the codebase. You will receive mentoring support from managers and senior developers to help develop your skills as realizing growth potential is a key goal.

Our ideal candidate has experience working with large web applications. They will know how to build reliable and performant web applications. Testing and code quality are also extremely important to us, so having a strong knowledge of testing and the different testing types is required.

• Build backend systems using Ruby on Rails stack.
• Understand product goals and feature requests and translate them into working software
• Work on large technical projects from design through implementation and delivery as part of a team
• Ensure high-quality, reliable software - including thorough testing.

• You are familiar enough with Ruby to discuss topics such as the Object Hierarchy and meta-programming features such as `method_missing`
• Experience with building performant and scalable Ruby applications.
• Ability to design data models and system architectures.
• Strong technical communication skills - including the ability to document decisions clearly and concisely
• Experience and understanding of common web vulnerabilities and how to mitigate them
• Understanding of software architecture, design patterns and best practices

• Experience with TypeScript, Vue.js, or React
• Experience with payments or payment systems
• Experience with integrating with third party APIs in a secure and fault-tolerant manner
• Understanding of database performance characteristics and data access patterns
• Familiarity with Monitoring and Observability techniques and platforms such as DataDog.
  

• We aim to keep our hiring process thoughtful and efficient, typically involving 3-4 stages depending on the role: an initial screening, a take-home exercise, a technical (team) interview, and a final interview with leadership. Throughout the process, the team evaluates candidates not only on technical skills but also on their alignment with team culture and potential for long-term growth. Beyond the Code: How to shine in coding exercises

• At Degica, we embrace remote work while also offering office space for those who prefer in-person collaboration
• 10 days regular vacation, additional 5 days summer, and 5 days winter vacation
• Paid birthday holiday
• Budget for self-learning allowance, to ensure our employees’ skills remain current
• Access to the O’Reilly Learning Platform
• Language training for Japanese/ English
• Twice a week office lunch