Senior Staff Machine Learning Engineer, (Machine Learning)

Affirm is a fintech company reinventing credit with transparent, no-hidden-fee buy-now-pay-later products. As a Senior Staff Machine Learning Engineer, you will define multi-year ML strategy, design and scale advanced ML systems, and partner with ML Platform, engineering, and product leaders to drive high-impact innovation across the organization.

• Define and drive multi-year, multi-team technical strategy for machine learning across Affirm.
• Lead design, implementation, and scaling of advanced ML systems, setting architectural direction.
• Partner with ML Platform, product, engineering, and risk leadership to shape long-term modeling capabilities.
• Provide broad technical leadership, mentoring senior engineers and spreading ML expertise.
• Drive clarity on ambiguous technical decisions and champion operational excellence.

• 10+ years experience researching, designing, deploying, and operating large-scale real-time ML systems.
• Proficiency in Python and ML frameworks including PyTorch and XGBoost.
• Experience with distributed frameworks such as Spark, Ray.
• Experience with ML tooling: Kubeflow, MLflow or equivalent.
• Deep expertise in neural network-based sequence modeling (Transformers, recurrent, attention-based models).
• Hands-on experience with large-scale distributed ML infrastructure (data ingestion, feature stores, training pipelines, model serving).