Senior Machine Learning Engineer (Fraud) @Affirm

Overview

Affirm is reinventing credit to make it more honest and friendly, providing consumers the flexibility to buy now and pay later without any hidden fees or compounding interest. The Senior Machine Learning Engineer will work on the ML Fraud team to build and improve machine learning systems that make real-time transaction decisions.

Key Responsibilities

• Lead development of new fraud prediction models using various approaches for tabular, graph, and behavioral data.
• Build and scale feature pipelines and training datasets from proprietary and third-party signals.
• Prototype new modeling ideas and features, run offline experiments, and drive the best-performing approaches into production.
• Integrate models into batch and/or real-time decision systems, improving reliability, latency, and operational robustness.
• Monitor model and data health, and assist in defining retraining/backtesting workflows.
• Implement foundational improvements to the model-building process.
• Collaborate across departments to define requirements and communicate results clearly.

Requirements

• 6+ years of experience in researching, training, tuning, and launching ML models at scale.
• Experience delivering impactful machine learning models in low latency live settings.
• Strong Python skills and experience writing production-quality code.
• Experience with models for tabular classification problems (e.g., LightGBM, XGBoost, CatBoost).
• Familiarity with deep learning frameworks (PyTorch preferred).
• Experience with distributed data processing or parallel compute frameworks (e.g., Spark, Ray).
• Knowledge of ML lifecycle tooling for training orchestration and model monitoring (e.g., Kubeflow, Airflow, MLflow).
• Strong communication skills for effective collaboration with a global engineering team.

Benefits

• 100% subsidized medical coverage, dental and vision for employees and dependents.
• Flexible Spending Wallets for technology, food, lifestyle needs, and family forming expenses.
• Competitive vacation and holiday schedules.
• Employee stock purchase plan (ESPP) enabling purchase of shares at a discount.

Location

This remote role is open only to candidates residing in Canada, specifically in Alberta, British Columbia, Manitoba, New Brunswick, Newfoundland and Labrador, Nova Scotia, Ontario, Prince Edward Island, or Saskatchewan.

How to Apply

Apply through the Affirm career page.

Deadline

Not stated.