Note: The job is a remote job and is open to candidates in USA. Reddit, Inc. is a community-driven platform that facilitates open conversations among its users. They are seeking a Machine Learning Engineer to design and implement optimization algorithms for their ads marketplace, focusing on auction mechanisms and ensuring marketplace quality.
Responsibilities
- Design and implement models and policies that:
- Compute bids for different optimization objectives (e.g., CPC, CPA, ROAS-based strategies)
- Pace budgets smoothly over time across accounts, campaigns, and ad groups while preventing overspend or underspend
- Allocate spend and auction participation intelligently across segments, surfaces, and time zones
- Translate product and marketplace goals into concrete optimization problems and constraints (e.g., ROI, revenue, delivery smoothness, fairness, and user experience)
- Partner with Ads Marketplace Quality to:
- Improve ad matching and ranking by incorporating new quality and relevance signals into bidding and auction decisions
- Inform policies around ad load and eligibility that protect user experience while increasing high-quality ad opportunities
- Collaborate closely with Ads Optimization to integrate new bid strategies and pacing mechanisms into the broader ads ecosystem and measurement stack
Skills
- 3–5+ years of experience building, deploying, and operating machine learning systems in production (for IC4, typically 5+ years)
- Strong programming skills in Python, Java, Go, or similar languages, with solid software engineering fundamentals
- Experience designing scalable data processing systems (e.g., Spark, Kafka, Airflow, BigQuery, Redis)
- Demonstrated ability to translate ambiguous product or business problems into solutions and to improve measurable metrics
- Evidence of stronger math and optimization skills than a generic MLE, such as: Degree or equivalent background in a quantitative field (math, physics, quantitative finance, economics, operations research, or similar)
- Work experience in optimization-heavy domains (e.g., bidding/auctions, pacing, pricing, logistics optimization, quantitative finance)
- Comfort reasoning about and implementing custom optimization logic (e.g., gradient-based methods, constraint handling), not just applying black-box tooling
- Experience with advertising/auction systems, online marketplaces, or search/ranking systems at scale, particularly in: Bidding, pacing, or budget optimization; Auction design, mechanism design, or marketplace quality; Campaign performance optimization (e.g., CTR/CVR, CPA, ROAS)
- Familiarity with large-scale, real-time decision systems and low-latency production environments
- Background in feature engineering, model optimization, and production monitoring for ML systems
- Experience collaborating with cross-functional partners (Product, DS, Eng) in Ads or marketplace contexts and leading projects from design through rollout
- Advanced degree (MS or PhD) in Computer Science, Machine Learning, Operations Research, Applied Math, or a related quantitative field
Benefits
- Comprehensive Healthcare Benefits and Income Replacement Programs
- 401k with Employer Match
- Global Benefit programs that fit your lifestyle, from workspace to professional development to caregiving support
- Family Planning Support
- Gender-Affirming Care
- Mental Health & Coaching Benefits
- Flexible Vacation & Paid Volunteer Time Off
- Generous Paid Parental Leave
- Equity in the form of restricted stock units
- Commission (depending on the position offered)
- Medical, dental, and vision insurance
- 401(k) program with employer match
- Generous time off for vacation
- Parental leave
Company Overview
Company H1B Sponsorship