About the Position

Senior Data Scientist

Ukraine, Ukraine

About the Team

At Sift, our Data Science team works at the core of our Digital Trust & Safety platform, helping customers stop fraud, abuse, and account takeover while protecting great user experiences. We partner closely with engineering, product, and go-to-market teams to turn large-scale behavioral data into practical machine learning improvements and customer value.

We are a forward-thinking team that challenges the status quo, values open and constructive feedback, and cares deeply about learning, rigor, and impact. We take pride in our work, not ourselves, and we believe machine learning is a powerful way to help internet businesses grow safely.

Responsibilities

Analyze fraud patterns, customer behavior, and model outcomes to identify opportunities for product and model improvements.
Partner with engineering and product teams to define evaluation metrics, investigate gaps in current product behavior, and propose practical improvements that drive customer value.
Design and run experiments on features, modeling approaches, and datasets to validate ideas and improve model performance.
Evaluate model quality through dataset analysis, error analysis, calibration, and score distribution investigations.
Build repeatable analyses, prototypes, and internal tools that support research, diagnosis, and operational decision-making.
Communicate findings and recommendations clearly across data science, engineering, and business stakeholders.

Requirements

Bachelor's degree in Computer Science, Statistics, Mathematics, a related technical field, or equivalent practical experience.
5+ years of relevant industry experience in data science, machine learning, analytics, or a closely related field.
Strong foundation in machine learning and data science best practices, with experience applying them to real-world problems.
Experience working with large datasets using tools such as Python, Jupyter, Pandas, PySpark, scikit-learn, PyTorch, TensorFlow, or similar technologies.
Comfort performing both deep analysis and lightweight prototyping to test ideas quickly.
Strong problem-solving skills and the ability to work effectively in ambiguous spaces with competing priorities.
Clear communication and collaboration skills, with a team-first mindset.

Nice to Have

Experience in fraud, risk, trust and safety, cybersecurity, or adjacent domains.
Familiarity with Java or another object-oriented programming language.
Experience partnering closely with software engineers to productionize analytical or machine learning improvements.

We Offer

Opportunity to work with a leading AI-powered fraud platform.
Be part of a team that helps leading global businesses grow fearlessly.
Commitment to long-term customer success and delivering safer, more seamless consumer experiences.

About the Company

Sift is the AI-powered fraud platform securing digital trust for leading global businesses. Our deep investments in machine learning and user identity, a data network scoring over 1 trillion events per year, and a commitment to long-term customer success help customers grow fearlessly while delivering safer, more seamless consumer experiences.

Senior Data Scientist

Job description