Senior Software Engineer (Sole Proprietor Development Department - Tokyo)
- Tokyo
- Partial Remote
- Full-time
- May 26, 2026
Overview
The Sole Proprietor Development Department, part of Money Forward Business Company, is dedicated to empowering individual workers by developing innovative solutions that simplify and enhance their professional lives.
Our mission, "Moving work and life forward for individual workers", drives us to create products that address the unique challenges faced by sole proprietors.
Our flagship offerings include Cloud Tax Return (クラウド 確定申告), a cloud-based tax filing solution that seamlessly integrates with the Money Forward ME personal finance app, providing users with a comprehensive view of their financial health. Additionally, Cloud Business Registration (クラウド 開業届) streamlines the business registration process, while Cloud Company Registration (クラウド 会社設立) facilitates company establishment with ease.
These products are designed to reduce administrative burdens, enhance efficiency, and ensure compliance with regulatory requirements, allowing sole proprietors to focus on their core business activities and achieve greater success.
We are looking for a full-stack engineer to join our team and be a part of our mission to provide our users with intuitive and user-friendly tools that adapt to their evolving needs.
Job satisfaction & Experience to be gained
Job Satisfaction
Drive Massive User Impact: Be an essential part of our mission to "Moving work and life forward for individual workers" by developing solutions like Cloud Tax Return and Cloud Business Registration that directly reduce administrative burdens and enhance efficiency for sole proprietors.
Full Product Ownership and Influence: Move beyond simple development to become a key strategic voice. You will collaborate closely with stakeholders and cross-functional teams to define, design, and influence the product's direction, not just build what you are told.
Thrive in an Open Culture: Work in a highly transparent and inclusive environment where bi-directional communication is actively promoted and open discussion across all topics is welcomed.
Experience Gained
Mandatory AI Innovation: Gain cutting-edge experience by working in a development environment where AI usage is explicitly recommended and mandatory, allowing you to leverage new technologies to drive efficiency and redefine quality standards.
Accelerated Career Growth: Fast-track your career with clear opportunities for project leadership and management, utilizing soft skills to mentor junior engineers and guide the team's development journey to the next level.
Diverse & Modern Tech Stack Mastery: Expand your skills across a diverse and robust full-stack environment, including backend technologies like Ruby on Rails, Kotlin, and Go, and modern frontend frameworks such as Next.js, TypeScript, and React.
Responsibilities and Duties
- Design, develop, and maintain scalable and robust full-stack applications.
- Collaborate with cross-functional teams to define, design, and ship new features.
- Ensure the performance, quality, and responsiveness of applications.
- Identify and correct bottlenecks and fix bugs.
- Help maintain code quality, organization, and automation.
- Mentor and guide junior engineers, fostering a culture of continuous learning and improvement.
- Participate in code reviews to maintain high standards of code quality.
Required Skills and Experience
- Minimum of 5 years of experience in software development.
- Minimum of 3 years of web application development experience, with proven experience with backend and frontend web frameworks.
- Experience with Ruby on Rails
- Demonstrated experience working in Agile teams.
- Strong problem-solving skills and ability to work independently and collaboratively.
- Product Mindset:
- Understand user workflows within the target domain and discuss specification validity
- Identify potential design risks by considering domain assumptions and constraints
- Decision Leadership:
- Ability to organize objectives, non-objectives, constraints, and risks to drive decision-making forward
- AI-Augmented Delivery
- Utilize generative AI/coding assistance tools to accelerate development while ensuring quality, safety, and maintainability
Preferred Skills and Experience
- Experience with Golang is preferred.
- Experience with leadership and management are preferred.
- Experience in AI development and/or experience in using AI tools to improve development processes.
- Money Forward recently announced our AI Strategy roadmap which focuses on improving AI-driven operational efficiencies, as well as integrating AI agents into our products to deliver better value to our users. (More information here)
Language Requirements
- English: Minimum conversational level (be able to conduct interviews in English)
- Japanese: Business level; (minimally conversational level *be able to conduct interviews in Japanese)
Technology Stack
- Backend: Rails, GraphQL, RSpec, Go, Kotlin, ActiveMQ
- Frontend: Next.js, TypeScript, React, GraphQL, Node.js, React Testing Library
- Database: MySQL, Redis
- Infrastructure: AWS(EKS), Docker, CircleCI, Datadog
Work Environment
At Money Forward, we provide an environment where we can create world-class services together, and we are looking forward to welcoming you.
- Provided PC Specs: We provide PCs equipped with the latest CPUs (MacOS or Windows). Custom-made PCs tailored to business requirements and replacements with the latest OS are also possible.
- Systems to Enhance the Development Environment: Peripheral devices necessary for work (such as displays, mice, keyboards) can be purchased as office supplies. Generally, you can choose from standard products (catalog), and if conditions are met, you can apply for non-standard products as well.
- Money Forward Library: We have a library system where you can freely borrow books, ranging from technical books to management books. Desired books can be purchased at the company's expense.
- Referral Driven: We cover the cost of recruitment meals. There is a referral reward system.
- Conference Participation Support: The company partially covers participation in domestic and international conferences, such as RubyKaigi and Google I/O.
About Money Forward
Money Forward, founded in 2012, strives to deliver exceptional value to users in various business domains. As a leading FinTech company, we offer over 40 services, ranging from personal finance management to B2B SaaS products.
We have been growing rapidly, and we are expanding our global hiring to help further expand the company. That means that we are open to hiring those with limited or no Japanese language proficiency.
Money Forward is one of Japan's hottest FinTech companies and it is now a great opportunity to be a part of one of our continued growths!
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