Staff Machine Learning Engineer (AI)

TL;DR

Staff Machine Learning Engineer (AI/AdTech): Designing and training advanced ML models for large-scale advertising ranking and optimization with an accent on deep neural networks, transformers, and reinforcement learning. Focus on optimizing high-dimensional embeddings, driving end-to-end model lifecycles, and shaping long-term modeling strategy across multiple advertising domains.

Location: San Francisco, CA; full-time telecommuting is an option. Must be US-based

Salary: $230,000 - $322,000 USD

Company

Reddit is a community-driven platform and one of the internet's largest sources of information, hosting over 100,000 active communities.

What you will do

• Design, develop, and train advanced ML models, including DNNs, transformers, and reinforcement learning systems for ad ranking and optimization.
• Lead the development of complex feature representations and high-dimensional embeddings.
• Drive the end-to-end model lifecycle, including system architecture, large-scale experimentation, and production deployment.
• Collaborate with product, data, and infrastructure teams to translate business objectives into scalable modeling solutions.
• Conduct advanced experiment design and causal analysis to evaluate model impact.
• Provide technical leadership and mentorship to ML engineers and define organization-wide modeling standards.

Requirements

• Master’s degree in Computer Science, Engineering, or a related quantitative discipline.
• 3+ years of experience in machine learning engineering or a related occupation.
• Proficiency in Python, Java, and Scala, and experience with C++, Go, or Rust.
• Experience with major ML frameworks, libraries, and large-scale data processing frameworks.
• Strong knowledge of applied statistics, hypothesis testing, and experiment design for online ML systems.
• Must be eligible to work in the US (implied by US-based benefits and pay transparency).

Nice to have

• Experience with marketplace dynamics, such as real-time bidding (RTB) or pacing control systems.
• Experience developing and optimizing online advertising systems (targeting, ranking).

Culture & Benefits

• Comprehensive healthcare and income replacement programs.
• 401k with employer match.
• Flexible vacation and paid volunteer time off.
• Generous paid parental leave and family planning support.
• Mental health, coaching, and gender-affirming care benefits.