Senior Software Engineer, Fraud Risk

5+ years of professional experience as an engineer At least 2 years of personal or professional experience with Ruby Production debugging expertise Strong sense of ownership Great communication skills Detail-oriented team player Business-level English proficiency Familiarity with statistical methods (logistic regression, GLMs) and machine learning (nice to have) Ability to perform exploratory data analysis (EDA) (nice to have) Experience with data ETL pipelines (nice to have) Comfort working with SQL (nice to have) Python, or any other major programming language (nice to have) Experience working in the credit card or payment industry (nice to have) Background in payment security or security systems (nice to have) Conversational-level Japanese proficiency (nice to have)

Designing, building, and maintaining software solutions for KOMOJU's fraud prevention processes Building robust antifraud solutions Creating merchant-facing features that provide visibility into transaction fraud signals Scaling systems to handle increasing complexity and traffic Converting ML models (e.g. merchant risk scorecards) into working code