Senior Machine Learning Engineer; ML Underwriting

Affirm – The Future of Credit

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.

Senior Staff Machine Learning Engineer, (ML Underwriting)

Join the affirm team as a Senior Staff Machine Learning Engineer and become a pivotal part of our innovative ML team. You will shape the future of machine learning, partner with ML Platform, product, engineering and risk leaders, give technical leadership, mentor engineers, and influence architecture and strategy.

• Define and drive multi-year, multi-team technical strategy for machine learning across affirm, aligning with company priorities and influencing partner team roadmaps.
• Lead the design, implementation, and scaling of advanced ML systems, setting architectural direction for complex initiatives and ensuring reliability, extensibility, and support for sophisticated workloads.
• Partner deeply with ML Platform, product, engineering, and risk leadership to shape long-term modeling capabilities, define new opportunities for ML impact, and guide infrastructure evolution required for next‑generation ML methods.
• Provide broad technical leadership across the ML organization, mentoring senior engineers, elevating design and code quality, and spreading ML expertise through documentation, talks, and cross‑org guidance.
• Drive clarity and alignment on ambiguous, high‑stakes technical decisions, resolving cross‑team tensions, balancing competing priorities, and exercising judgment optimized for the broader engineering organization.
• Champion operational and system excellence at the area level, owning long‑term health, availability, and evolution of critical ML systems, and ensuring robust testing, monitoring, and reliability practices across teams.

• 10+ years of experience researching, designing, deploying, and operating large‑scale, real‑time machine learning systems, with proven record of technical innovation and measurable business impact. Relevant PhD can count for up to 2 YOE.
• Experience leading end‑to‑end ML system design, from data architecture and feature pipelines to model training, evaluation, and production deployment. Use of distributed frameworks such as Spark, Ray, or similar large‑scale data processing systems.
• Proficiency in Python and ML frameworks, including PyTorch and XGBoost. Experience with ML tooling for training orchestration, experimentation, and model monitoring, such as Kubeflow, MLflow, or equivalent internal platforms.
• Strong understanding of representation learning and embedding‑based modeling. Deep expertise in neural network‑based sequence modeling, including Transformers, recurrent, or attention‑based models, and multi‑task learning systems. Comfortable designing and optimizing models that learn from sequential or temporal event data at scale.
• Hands‑on experience with large‑scale distributed ML infrastructure, including streaming or batch data ingestion, feature stores, feature engineering, training pipelines, model serving and inference infrastructure, monitoring, and automated retraining.
• Strong technical leadership: defining long‑term strategy, guiding research direction, and aligning work across teams. Recognized as a trusted expert who can drive clarity and execution in ambiguous problem spaces.
• Exceptional judgment, collaboration, and communication skills, enabling effective technical discussions with engineers, researchers, and executives. Mentor senior engineers, foster technical excellence, and contribute to a culture of continuous learning.
• Strong verbal and written communication skills that support effective collaboration across our global engineering organization.
• Equivalent practical experience or a Bachelor’s degree in a related field.

Pay Grade – R

Equity Grade – 15

Employees new to affirm typically start at the beginning of the pay range. Base pay is part of a total compensation package that may include equity rewards, monthly stipends for health, wellness and tech spending, and benefits.

USA base pay range (CA, WA, NY, NJ, CT) per year: $260,000 - $310,000

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