Senior Data Science Engineer

Remote OK - Anywhere in Japan
Full-time
June 5, 2025

Team Missions

To drive value-added 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

Process, analyze, and create visualizations for both structured and unstructured data
Design and maintain algorithms for predictive modeling and recommendations
Collaborate with data engineers, product managers, and stakeholders to build robust production systems

Required Qualifications

Bachelors in a quantitative field such as Computer Science, Mathematics, Statistics, Machine Learning, or equivalent
Excellent verbal and written communication skills in English and/or Japanese
More than five years of work experience as a data scientist, software engineer, statistician, or equivalent role
Experience in at least one primary language (e.g., Java, Scala, Python) and SQL (any variant)

Preferred Qualifications

Masters or PhD in a quantitative field such as Computer Science, Mathematics, Statistics, Operations Research, Machine Learning, or equivalent
More than seven years of experience as a data scientist, machine learning engineer, or equivalent role
Experience building and maintaining microservices
Experience with Big Data technologies like BigQuery, Spark, Hadoop, AWS Redshift, Kafka, or Kinesis streaming
Extensive knowledge and work experience in recommendation systems, deep learning, NLP, and optimization
Experience with AWS services such as Glue, SageMaker, Athena, and S3
Experience designing and conducting A/B and hypothesis tests

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About PayPay

PayPay, a FinTech company that has achieved more than 69M users (as of May 2025) within around six years since its launch in 2018, is rapidly expanding its business scale as a payment platform used by approximately one out of every two smartphone users in Japan.

The company has a diverse team of professionals from more than 50 countries and is building a world-class engineering organization.

PayPay's biggest competitor is "cash". They are seeking people who can accept this challenge positively, brush up on the product at a tremendous speed that other companies could never achieve, and who are passionate about promoting and spreading such a financial life platform in a short time along with professionalism.

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
PayPay is committed to maintaining a "Day 1" mindset, bringing to life visions of the future that no one else can even imagine. At PayPay, we provide an environment where everyone can deliver outstanding performance as professionals, through a flexible work style that includes remote and office.
Work style
- Super Flex Time with no core time
- In principle, from 9:00am-5:45pm (actual working hours: 7h45m + 1h break)