Senior Machine Learning Engineer in Financial Services
Japan’s largest mobile payments platform (~75M users); SoftBank/LY Corporation fintech JV; 40% equity holder of Binance Japan.
Maintainer signals as of 8/20/2026
About PayPay
PayPay Corporation is a Tokyo-based fintech company operating Japan’s leading QR/mobile payment service, founded 2018 as a SoftBank/Yahoo Japan (LY Corporation) joint venture, with banking (PayPay Bank), insurance and securities offerings. In October 2025 PayPay acquired a 40% equity stake in Binance Japan, making the crypto exchange an equity-method affiliate.
Skills
Candidate Availability
Required and preferred rules are kept separate and reflect the wording in the original posting.
About the Role
You will lead the design and development of credit-scoring, risk-management, and marketing models for financial services. You will define business and quality requirements, design machine-learning system architectures, guide engineering teams through product integration, and improve MLOps for training, evaluation, monitoring, and continuous improvement.
Requirements
- Advanced expertise in AI, machine learning, mathematical engineering, or mathematical statistics
- At least approximately three years of practical experience developing and operating machine-learning prediction models
- Experience developing models for credit scoring, risk management, fraud detection, marketing optimization, or user behavior prediction
- Experience defining machine-learning system quality requirements
- Experience leading end-to-end system architecture design and product or process integration
- Team software development and leadership experience using Python or similar technologies
- Financial or payments experience
- PhD in mathematical engineering, statistics, computer science, or a related field
- Experience with large-scale data processing pipelines on GCP, AWS, or similar cloud environments
- Experience introducing or operating MLOps platforms such as Kubeflow or MLflow
- Experience leading teams of approximately 5 to 10 people
Responsibilities
- Design and develop credit, risk-management, and marketing models
- Define business requirements and select suitable prediction models
- Design system architectures for AI and machine-learning applications
- Define requirements for prediction accuracy, explainability, stability, security, and operating cost
- Integrate models safely into products and business processes
- Lead development direction, code reviews, and testing strategies
- Collaborate with engineers, data scientists, and data analysts
- Update MLOps architecture for model training, evaluation, monitoring, and continuous improvement
- Drive operational improvements across financial-services machine-learning systems
Benefits
- Hybrid workstyle
- Super flextime with no core hours
- Annual paid leave of 14 days in the first year
- Personal leave of 5 days annually
- Health insurance
- Employees' pension insurance
- Employment insurance
- Workers' compensation insurance
- Corporate defined-contribution pension plan