Affirm

Affirm

Senior Machine Learning Engineer (Fraud)

Remote Canada · Senior

Sponsorship not specified$153k-$213kDetected 22 hours ago
PythonRESTMachine LearningDeep LearningPyTorchSparkAirflowA/B TestingCommunicationCollaboration

About the role

  • Affirm is reinventing credit to make it more honest and friendly, giving consumers the flexibility to buy now and pay later without any hidden fees or compounding interest.
  • Pay Grade - N Equity Grade - 6 Employees new to Affirm typically come in at the start of the pay range.

Responsibilities

  • You will lead development of new fraud prediction models using a mix of approaches for tabular, graph, and behavioral data
  • You will build and scale feature pipelines and training datasets from proprietary and third-party signals, partnering with data and platform teams when needed.
  • You will prototype new modeling ideas and features, run offline experiments, and drive the best-performing approaches into production with appropriate risk controls.
  • Identify and implement foundational improvements to how the team builds models.
  • You will collaborate across Engineering, Fraud Analytics, Product, and ML Platform to define requirements, evaluate tradeoffs, and communicate results clearly to both technical and non-technical audiences.
  • Experience building and evaluating models for tabular classification problems (preferably gradient-boosted decision trees like LightGBM/XGBoost/CatBoost, or similar).

Requirements

  • You have 6+ years experience researching, training, tuning and launching ML models at scale.
  • Relevant PhD can count for up to 2 years of experience.
  • Experience with ML lifecycle tooling for training orchestration, experimentation, and model monitoring (e.g., Kubeflow, Airflow, MLflow, or equivalent internal platforms).
  • What we look for - You have 6+ years experience researching, training, tuning and launching ML models at scale.
  • You have mastered taking a simple problem or business scenario into a solution that interacts with multiple software components, and executing on it by writing clear, easily understood, well tested and extensible code.
  • You are comfortable navigating a large code base, debugging others' code, and providing feedback to other engineers through code reviews.

Nice to have

  • Experience working with distributed data processing or parallel compute frameworks (Spark preferred
  • Ray/Dask or similar).

Compensation

  • Employees new to Affirm typically come in at the start of the pay range.
  • CAN base pay range per year: $153,000 - $213,000

Benefits

  • You will instrument and monitor model and data health, and help define retraining/backtesting workflows as fraud patterns evolve.
  • Track record of delivering high impact machine learning models in a low latency live setting
  • Experience with a deep learning framework (PyTorch preferred).

Company info

  • Proficient in using AI-powered developer tools (e.g., Claude Code, Cursor, or similar) to accelerate iteration, debugging, and code quality as part of day-to-day development workflows.

This listing is sourced directly from Affirm's careers page and normalized into a canonical job model.