Product Science Engineer

Remote OK - Anywhere in Japan
Full-time
January 16, 2024

Team Missions

To drive product improvements by engineering systems founded on a scientific understanding of user and merchant behavior
Our scope of work spans engineering, product science, data science, machine learning, statistical inference, optimization, and BI analytics

Responsibilities

Drive product innovations and improvements with scientific research and analysis
Conduct experiments and hypothesis testing to understand user and merchant behavior
Measure and monitor product KPIs to identify product opportunities and successes
Process, analyze, and create visualizations for both structured and unstructured data
Collaborate with engineers, product managers, designers, and stakeholders to quickly iterate the product development cycle

Required Qualifications

Bachelors in a quantitative field such as Computer Science, Mathematics, Statistics, Machine Learning, or equivalent
Solid background in experimental design, data analytics, and scientific research
Excellent verbal and written communication skills in English and/or Japanese
More than three years of experience as a data scientist, product scientist, machine learning engineer, or equivalent role
Proficiency in at least one primary language (e.g., Java, Scala, Python) and SQL (any variant)
Experience working effectively with cross-functional teams

Preferred Qualifications

Masters or PhD in a quantitative field such as Computer Science, Mathematics, Statistics, Operations Research, Machine Learning, or equivalent
More than five years of experience as a data scientist, product scientist, machine learning engineer, or equivalent role
Experience with Big Data technologies like BigQuery, Spark, Hadoop, AWS Redshift, Kafka, or Kinesis streaming
Experience with AWS services such as Glue, SageMaker, Athena, and S3
A track record of working in a fast-paced environment and dealing with ambiguous requirements
Experience designing experiments with causal inference

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About PayPay

PayPay is a FinTech company that has grown to over 75M (as of August 2026) users since its launch in 2018. Our team is hugely diverse with members from over 50 different countries.

PayPay dares to believe that they do not need a clear vision to create a future beyond our imagination. PayPay will always stay true to their roots and realize a vision (future) that no one else can imagine by constantly taking risks and challenging themselves. 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. PayPay is looking for people who can embrace this challenge, refresh the product at breakneck speed and promote PayPay with professionalism and passion.

Japanese Language Policy
At PayPay, there is a mixture of Japanese and English spoken. Around 80% of their product team’s discussions happen in English, and they have technical interpreters and translators on staff to facilitate any translation necessary. Some members can speak both English and Japanese, but some can only speak either English or Japanese.

PayPay doesn’t have an official shared language, but in practice English tends to be the primary language used for internal communications and technical discussions like code reviews.

Instead of requiring that everyone be able to speak a specific language, PayPay expects an ability to communicate with mutual respect and a drive to ensure that you’re understood. The product team values proactive communication highly.
Visa Sponsorship
PayPay sponsors visas for applicants from overseas.
Paid Leave
- Days Off: Saturdays and Sundays. National holidays. Year-end and New Year holidays.
- Holidays: Annual paid leave, congratulatory or condolence leave, maternity leave and etc.
Benefits
🌎 Translation/interpretation support (EN<>JP)

🧡 Support for translation or other administrative tasks in Japanese

👍 Support from bilingual PIC for engineers

🇯🇵 Free Japanese lessons on company time

💻 PC and phone are given (based on the company’s regulations)

👩‍🎓 Training Program: We have various training programs for different kinds of needs

💜 Social security/insurance benefits included

💛 Defined contribution pension system (TBC)

🏥 Health insurance

🚃 Transportation coverage (up to ¥150,000/mo)
Engineer Interview Process
PayPay's Hiring process are as below:
- Application Review (English CV is required)
- Coding Test or Take Home Assignment (only applied to required positions)
- 3-4 Interviews (including both technical and behavioral interviews)
- Offer Meeting
Remote Work
Hybrid Workstyle (flexible working style including Remote and office)

※ You will be expected to work both in the office and remotely, in alignment with organizational guidelines and team objectives.
Work style
- Super Flex Time with no core time
- In principle, from 9:00am-5:45pm (actual working hours: 7h45m + 1h break)