Senior Machine Learning Engineer - Ranking

QuinStreet is a pioneer in powering decentralized online marketplaces that match searchers and consumers with brands. The role involves advancing algorithms for ordering, prioritization, and personalization, with a focus on ranking systems that enhance user experience and business outcomes.

Responsibilities:

• Design and improve ranking systems through rigorous measurement and experimentation; translate broad goals into clear metrics and deliver steady, validated gains
• Advance evaluation practices (clean test design, offline & online alignment) and help teams make evidence-based decisions
• Build high-value signals and features with reliable offline/online pipelines and robust monitoring. Incorporate content understanding signals such as text/image/metadata
• Make uncertainty-aware decisions; handle drift and calibration so models remain stable and trustworthy over time
• Partner with Engineering, Product, Business and Analytics to ship resilient solutions end-to-end

Requirements:

• Advanced degree (MS/PhD) in CS, Statistics, or related field, with 3+ years post-PhD or 5+ years industry experience
• Strong foundations in applied ML, statistics, and optimization with demonstrated impact in ranking/recommendations
• Proficiency in Python and solid software engineering practices (testing, CI/CD)
• Experience working with large-scale datasets, distributed systems, and latency-sensitive production ML
• Clear communication, cross-functional collaboration, and an ownership mindset
• Demonstrated success in delivering production-grade ranking systems with measurable business impact
• Track record building feature/signals pipelines, feature stores, and observability for ML systems
• Depth in experimentation and metrics design, including large-scale A/B testing and variance reduction