PayPay is a rapidly growing FinTech company with over 70 million users and a diverse team from over 50 countries. We are seeking a Senior Data Scientist to lead the development of novel machine learning systems for credit modeling and default risk prediction. This role involves working with petabyte-scale datasets, building high-throughput, low-latency production systems, and collaborating with innovative engineering teams to implement ML functionalities. You will drive the roadmap for ML applications in credit, identify opportunities, showcase system benefits to stakeholders, and own the model building process and infrastructure. We value speed, commitment, logical thinking, curiosity, and problem-solving.
Must have:
8+ years of software engineering experience
Proven track record in architecting and deploying ML systems
Experience with complex, scalable, high-throughput ML pipelines
Ability to explain ML concepts to technical audiences
Strong bias for action and 'get things done' attitude
Ability to maintain high performance in a fast-paced environment
Master's degree in Computer Science, Engineering, Mathematics, or related field
Good to have:
Working knowledge of PyTorch, Tensorflow, or similar frameworks
Working experience with AWS SageMaker or Google Vertex
Perks:
Social Insurance (health insurance, employee pension, employment insurance and compensation insurance)
PayPay is a FinTech company that has grown to over 70M (as of July 2025) users since its launch in 2018. Our team is hugely diverse with members from over 50 different countries.
OUR VISION IS UNLIMITED_
We dare to believe that we do not need a clear vision to create a future beyond our imagination. PayPay will always stay true to our roots and realize a vision (future) that no one else can imagine by constantly taking risks and challenging ourselves. With this mindset, you will be presented with new and exciting opportunities on a daily basis and have the opportunity to grow and reach new dimensions that you could never have imagined. We are looking for people who can embrace this challenge, refresh the product at breakneck speed and promote PayPay with professionalism and passion.
※ Please note that you cannot apply or be selected in parallel with PayPay Corporation, PayPay Card Corporation and PayPay Securities Corporation.
Job Description
We are looking for a leader with a passion to develop novel machine learning software systems for credit modeling and default risk prediction, deploy the systems to production, and test them to ensure all users and merchants needs are covered.
You will perform ETL to build model features using petabyte-scale datasets and develop high throughput and low latency systems to serve models in production touching the lives of more than 65 million customers every day. You will collaborate with highly innovative engineering teams to put machine learning functionalities into production systems that we build in-house.
We are looking for someone who oozes passion, ownership, and a love of building great things. The Product and Engineering teams will rely heavily on your build. You'll have a ton of trust and responsibility. So, if challenges excite you, and you're ready for a big one, let us know.
Responsibilities
Drive a roadmap that applies Machine Learning technologies to content discovery, engagement, recommendation, predication, risk underwriting etc.
Work with the leadership team to identify opportunities for using ML and drive solutioning in areas of Credit
Work with stakeholders to show them the benefits of using your system and driving adoption of the product
Designing scalable and deployable machine learning solutions
Define performance and validation metrics and coach the team to achieve these
Introduce and own the process of model building and the infrastructure behind it
Qualifications
8+ years of software engineering experience and a proven track record of successfully architecting and taking ML systems to production.
Designed and built multiple complex, scalable, high throughput, low latency streaming/batch processing machine learning pipelines for both data flows and algorithm execution
Ability to explain and present analyses and machine learning concepts to a broad technical audience
Have an extreme bias towards action. Basically, have the “Get Things Done” type of attitude.
Be able to maintain high-performance within a high-energy and fast-paced work environment.
You have a master degree or equivalent in Computer Science, Engineering, Mathematics or related field
Working knowledge of PyTorch, Tensorflow or other similar frameworks is a plus
Working experience of AWS SageMaker, Google Vertex is a plus
Portrait
Unparalleled speed: Discover for yourself the important things that need to be done and implement ways to reach the best results at the fastest speed possible for the organization
Commitment: As a professional, commit to the growth and business goals of the organization and create impactful results by your ownership
Logical thinking: Think logically and structurally to bring real communication
Curiosity and questioning mind: Keep your curiosity about new things and your challenges along with a continuous questioning mind and enjoy such circumstances in a future-oriented manner
Problem solving: Take a proper approach towards both explicit and potential business/organization challenges to lead solutions involving others
Hybrid Workstyle (flexible working style including Remote and office) ※There are no fixed rules regarding office attendance in Product group; it depends on each individual's discretion.
In principle, 9:00am-5:45pm (actual working hours: 7h45m + 1h break)
Holidays
Every Sat/Sun/National holidays (In Japan)/New Year's break/Company-designated Special days
Paid leave
Annual leave (up to 14 days in the first year, granted proportionally according to the month of employment. Can be used from the date of hire)
Personal leave (5 days each year, granted proportionally according to the month of employment) *PayPay's own special paid leave system, which can be used to attend to illnesses, injuries, hospital visits, etc., of the employee, family members, pets, etc...
Salary
Annual salary paid in 12 installments (monthly)
Based on skills, experience, and abilities
Reviewed once a year
Special Incentive once a year *Based on company performance and individual contribution and evaluation
Late overtime allowance
※Payroll payment can be changed to digital salary payment “PayPay Paycheck” for an amount set by you
Benefits
Social Insurance (health insurance, employee pension, employment insurance and compensation insurance)
PayPay is a fintech company that has grown to over 65M users since its launch in 2018. Our team is hugely diverse with members from over 50 different countries. We are looking for people who can embrace this challenge, refresh the product at breakneck speed and promote PayPay with professionalism and passion.